From owner-mpi-comm@CS.UTK.EDU Mon Nov 23 16:08:35 1992 Return-Path: Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA26326; Mon, 23 Nov 92 15:50:10 -0500 Received: from THUD.CS.UTK.EDU by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA26317; Mon, 23 Nov 92 15:50:05 -0500 From: Jack Dongarra Received: by thud.cs.utk.edu (5.61++/2.7c-UTK) id AA06935; Mon, 23 Nov 92 15:50:04 -0500 Date: Mon, 23 Nov 92 15:50:04 -0500 Message-Id: <9211232050.AA06935@thud.cs.utk.edu> To: mpi-comm@cs.utk.edu Subject: mpi committees and mailing list Status: R The following mailing lists have been set up. mpi-comm@cs.utk.edu Whole committee mpi-intro@cs.utk.edu Introduction subcommittee mpi-pt2pt@cs.utk.edu Point-to-point communication subcommittee mpi-collcomm@cs.utk.edu Collective communication subcommittee mpi-ptop@cs.utk.edu Process topology subcommittee mpi-lang@cs.utk.edu Language binding subcommittee mpi-formal@cs.utk.edu Formal language description subcommittee mpi-envir@cs.utk.edu Environment inquiry subcommittee All mail will be collected and can be retrieved by sending email to netlib@ornl.gov and in the mail message typing: send mpi-comm from mpi send mpi-intro from mpi etc. Also try: send index from mpi I'm in the process of collecting information on how the HPF committee operates and will pass along the details in the next few days. I would like to suggest January 6 - 8 for the next meeting in Dallas at the airport hotel. We should plan on starting around 1:00 on January 6th and finishing around 3:00 on January 8th. Below is a list of the subcommittees as I have them from our meeting last week. Please let me know if you have any changes. Regards, Jack Introduction Subcommittee ---------------------- Jack Dongarra - Chair dongarra@cs.utk.edu Daniel Frye danielf@kgnvma.vnet.ibm.com Tony Hey ajgh@ecs.soton.ac.uk Rusty Lusk lusk@mcs.anl.gov Steve Zenith zenith@kai.com Point-To-Point Communication Subcommittee ----------------------------------------- Marc Snir - Chair snir@watson.ibm.com Scott Berryman berryman@cs.yale.edu Jack Dongarra dongarra@cs.utk.edu Al Geist geist@msr.epm.ornl.gov Adam Greenberg moose@think.com Bill Gropp gropp@mcs.anl.gov Leslie Hart hart@fsl.noaa.gov Rolf Hempel hempel@gmd.de Tom Henderson hender@fsl.noaa.gov Bob Knighten knighten@ssd.intel.com Oliver McBryan mcbryan@piper.cs.colorado.edu Peter Rigsbee par@cray.com David Walker walker@msr.epm.ornl.gov Collective Communication Subcommittee ------------------------------------- Al Geist - Chair geist@msr.epm.ornl.gov Leslie Hart hart@fsl.noaa.gov Jon Flowers jwf@parasoft.com Adam Greenberg moose@think.com Bob Knighten knighten@ssd.intel.com Steve Otto otto@cse.ogi.edu Peter Rigsbee par@cray.com Marc Snir snir@watson.ibm.com David Walker walker@msr.epm.ornl.gov Process Topology Subcommittee ----------------------------- Rolf Hempel - Chair hempel@gmd.de Jon Flowers jwf@parasoft.com Tom Henderson hender@fsl.noaa.gov Oliver McBryan mcbryan@piper.cs.colorado.edu Steve Otto otto@cse.ogi.edu Lew Tucker tucker@think.com Language Binding Subcommittee ----------------------------- Scott Berryman - Chair berryman@cs.yale.edu Bruce Leisure bleasure@kai.com Formal Language Description Subcommittee ---------------------------------------- Steve Zenith - Chair zenith@kai.com Tony Hey ajgh@cs.ston.ac.uk Rusty Lusk lusk@mcs.anl.gov Environment Inquiry Subcommittee --------------------------------- Bill Gropp - Chair gropp@mcs.anl.gov Daniel Frye danielf@kgnvma.vnet.ibm.com From owner-mpi-comm@CS.UTK.EDU Tue Nov 24 15:37:43 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA02830; Tue, 24 Nov 92 15:37:43 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA19627; Tue, 24 Nov 92 15:12:24 -0500 Received: from antares.mcs.anl.gov by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA19622; Tue, 24 Nov 92 15:12:21 -0500 Received: from godzilla.mcs.anl.gov by antares.mcs.anl.gov (4.1/SMI-GAR) id AA25860; Tue, 24 Nov 92 14:12:19 CST From: gropp@antares.mcs.anl.gov (William Gropp) Received: by godzilla.mcs.anl.gov (4.1/GeneV4) id AA11600; Tue, 24 Nov 92 14:12:17 CST Date: Tue, 24 Nov 92 14:12:17 CST Message-Id: <9211242012.AA11600@godzilla.mcs.anl.gov> To: mpi-comm@cs.utk.edu Subject: Test Implementation of the Draft Standard We have completed a first and rough draft of a test implementation. We have included (and run!) three sample programs written in MPI on a sun network and on an Intel ipsc/i860. It is available by anonymous ftp from info.mcs.anl.gov in pub/mpi . The README file there gives more information, including how to get, install, and run the examples. This is a rough draft; the file mpi.man.ps.Z contains a description of the implementations architecture and man pages for all of the routines. We will be updating this implementation with additional examples and fewer restrictions soon. Enjoy! Bill Gropp and Rusty Lusk From owner-mpi-comm@CS.UTK.EDU Tue Nov 24 17:07:49 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA06915; Tue, 24 Nov 92 17:07:49 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA21596; Tue, 24 Nov 92 16:45:52 -0500 Received: from THUD.CS.UTK.EDU by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA21572; Tue, 24 Nov 92 16:45:38 -0500 From: Jack Dongarra Received: by thud.cs.utk.edu (5.61++/2.7c-UTK) id AA21258; Tue, 24 Nov 92 16:45:35 -0500 Date: Tue, 24 Nov 92 16:45:35 -0500 Message-Id: <9211242145.AA21258@thud.cs.utk.edu> To: mpi-comm@cs.utk.edu Subject: working procedures Chuck Koelbel has passed on some notes from the HPF experence. I think we will find them useful in carring out our meetings. Jack HPFF Working Procedures HPFF never had an explicit vote on adopting any operating procedures. We did, however, informally adopt the following rules. General Organization Most of the technical details were hammered out in subgroups, which made the base proposals. The main group would discuss these proposals and (usually) adopt them. In practice, lots of the technical discussions were done on email lists. Keeping those lists public was a big part of the openness of the forum. For a while, each subgroup brought its own proposal as handouts. Eventually, we ended up with a unified draft thanks to Dave Loveman. The intent (which we never lived up to) was that all proposals discussed at a meeting would be in that draft. Despite always having a loose proposal or two, the draft was extremely useful - among other things, it made editing a final report possible. Main Group / Plenary Session Matters For running discussions, we used loosely-enforced Robert's Rules of Order. Basically, we didn't stand on formalities unless the discussion was becoming unruly. Some of the more often-invoked rules: 1. Moving and voting on amendments before the main proposal. Basically, this kept the discussions focussed. 2. Motions coming out of committee (subgroup) are automatically seconded; others need a second from the floor. 3. Triply-nested amendments are not allowed. This keeps the confusion down. Generally, whoever was making the presentation ran the discussion, recognized comments from the floor, etc. Ken usually came in after the meat of the discussion to run the votes. Peer pressure was fairly effective at keeping people from filibustering (I think once there was a call to limit discussion). More common was lots of people wanting to make comments - this was handled by the presenters, usually by saying "OK, let's go clockwise around the table". Organizations were limited to 2 attendees each (not enforced, but no major problems). We passed around an attendence sheet at each meeting to keep track of who was there; because of various planning problems, I recommend using a pre-registration scheme ("send email to xxx@yyy if you plan to attend"). Organizations were asked to commit to having the same attendee at every meeting, and this was generally followed. It's very important to have this kind of continuity in attendees, else we would have spent too much time in remedial education. Each organization (school, company, lab) got one vote - note this was on an organization basis, not a person. We didn't have trouble with cheating on this rule - just make sure the representatives from an organization have agreed on who is voting. An organization was eligible to vote if it had attended 2 of the last 3 meetings, counting the current meeting (i.e. you could attend every other meeting and still vote; you could not vote at your first meeting). Obviously, we couldn't enforce this rule at the first two meetings. Accepting a section of the HPF language spec was a multi-step process. 1. Someone wrote a draft specification; often there were a couple drafts. Details of these were hashed out in the subgroup. 2. First Reading: The subgroup leader (or occasionally the draft author) presented the subgroup-approved draft to the main group. When there was controversy, it was usually pointed out. The main group discussed, suggested changes (sometimes), and held a series of "straw votes" on the proposal. All attendees were eligible to vote in straw votes, which were not binding on the subgroups. 3. More subgroup discussion, both electronic and in person at the next meeting, producing a revised proposal. 4. Second Reading: The subgroup leader presented the revised proposal to the main group. Sections that were substantially the same as the original (or an alternative presented at the first reading) were amended by motion and eventually voted on. Eligibility for votes was as explained above. Major additions (for example, when PURE functions were added to FORALL between meetings) were treated as first readings at this point. Often most of the proposal was accepted, and a few sections were sent back to subgroup for more work; these came back as second readings at the next meeting. 5. Once a section was accepted at second reading, it was "frozen" until the end of the HPFF process. Revisions were only allowed for clarity or when new information surfaced (like discovering that the draft was self-contradictory). This limitation was enforced as strictly as we could, to avoid backtracking. 6. At the end of the process (December), we promised to allow reconsideration of any feature. See also the discussion of the Journal of Development below. Subgroup Matters Subgroups met independently of the main body, usually the afternoon and evening of the day before. The leader of the subgroup ran these meetings using whatever style he or she was comfortable with. Most of us took votes from whoever showed up, and ran a pseud-democratic style. Also, there was a mailing list for each subgroup where most of the discussions went on. Each subgroup was devoted to one topic from the following list: Data distribution FORALL and other parallel statements Fortran 90, storage & sequence association, and the HPF subset Intrinsic functions Parallel I/O EXTRINSIC (nee LOCAL, nee FOREIGN) functions The groups met in parallel, which caused a little friction but was logstically unavoidable. When a subject straddled two groups (like intrinsic functions for enquiring about distributions), the subgroup leaders would talk to each other and decide who would handle it - this often led to minor anti-turf battles (also known as "after you" deadlock). Both groups would act as sanity checks on the results. When it came time to write the draft, each subgroup became a chapter. The subgroup leader was the editor (and usually major author) of the chapter, and was responsible for making sure the chapter reflected the decisions made in the subgroup and in committee. Logistical Matters Meetings were 2.5 days, starting Wednesday afternoon, in Dallas (there were exceptions to this for logistical reasons, but we would have prefered to keep them all on this schedule). A typical schedule was Wednesday 1:30-6:00 Subgroup meetings, about 3 going on in parallel (reserve 4 "breakout" rooms with the hotel, fo 10-20 people each) 6:00-7:30 Unofficial dinner break (usually the subgroup leaders ate together & planned the meeting agenda) 7:30-10:30 More subgroup meetings (subgroup leaders usually ended up staying up late to revise drafts) Thursday 9:00-12:00 Full group meeting (coffee breaks at natural breaks) 12:00-1:30 Lunch (provided) 1:30-6:00 Full group meeting (and coffee breaks) 6:00-8:00 Dinner (attendees pay, but hotel provided transport to area restaurant) 8:00-10:00 (Sometimes) Full group meeting (when no full meeting, subgroups usually met instead) Friday 9:00-12:00 Full group meeting (and coffee breaks) 12:00-1:30 (Sometimes) Lunch (provided if we thought the meeting would last long) 1:30-3:00 (Sometimes) Full group meeting We tried to finish as early as possible on Friday, to allow people to catch flights. Since we scheduled all the meetings early on, we set up a contract with the hotel. I didn't handle the details, but I think this saved us a little money and a lot of aggravation (talk to Theresa Chatman if you need more info). At any rate, this is a great thing for someone on your staff to set up. We financed the meetings primarily from a per-meeting fee of $95 ($75 if we didn't have lunch the second day) per attendee. Ken offered to foot the bill for academics to attend, based on the expectation of NSF funds. We're still waiting on those funds; highly recommend that you don't make such offers without first getting the cash. Documentation The Draft: The earlier you have one the better. David Loveman served as our general editor, collecting the chapters and trying to smooth format details. I contributed the introduction and credits, mainly cribbed from meeting notes and other announcements. Guy Steele contributed a set of macros for BNF syntax and reproducing code segments. We tried to find some formatting from an ANSI standard, but no dice. Toward the end of the process, version control became a problem. We (tried to) set up the following framework: 1. David had the "official" version of the draft. He set deadlines for receiving the chapters, and edited for formatting. 2. David sent me the whole document when all the chapters were done. I LaTeXed it to check for system dependences (never a problem) 3. I sent the document to the "core" mail group (see below), put it out for anonymous FTP, and announced it on the net. 4. Any further changes were supposed to be made to David's edited copy, not the original version (this to make the next round of edits easier). The system worked pretty well, until the final draft when the wrong version of Chapter 6 got distributed... Each subgroup wrote one chapter, generally written and/or edited by the subgroup leader. While the meetings were going on, the draft contained all proposals still under consideration (Guy provided a "\alternative" macro that marked sections as being alternatives to each other). Also, the author of each section was identified in a footnote at the beginning of the section, along with the date (and occasionally other version information). In the current draft, we've moved summaries of some discarded proposals to the "Journal of Development" (primarily the ones dropped for lack of time). All proposals exist in the archives; we may put together a "rationale" document to explain some of the more controversial decisions. We're also planning to move the authorship information from footnotes to the credits chapter in the December draft. It's too early to know how this organization will work for the reader, but the modularity has helped in writing the document. Other lessons from the draft: 1. Make sure the chapter authors realize they are writing a draft chapter, not a stand-alone document. 2. Make sure the person in charge of the credits chapter has plenty of time to work on it (I spent 50% of my time for a week appeasing various corporate egos, wording things right, and checking spelling of names). 3. Proofread the document before sending it out - both spell checking and careful chapter reading. Mailing lists: Every subgroup had its own mailing list. Those lists are where most of the technical action happened; they were very high-volume (final total was something like 1.5Mb of archived messages). On top of that, there was a list for everybody in the world interested in HPF, and another for the "core" group. The "everybody" list was used for the meeting minutes and a few miscellaneous announcements. The core group list was primarily for the meeting attendees, but a few others were also on it for political and/or practical reasons (for example, Gil Weigand and Theresa Chatman were both on the list); it got meeting details, and copies of the various proposals before the meetings. All lists were kept at cs.rice.edu (there were a couple smaller lists other places, including a European list at GMD and several local lists for particular campuses). People could add or delete themselves to/from any of the lists by mailing to another mail alias at Rice. Automating this was a huge win (although I got 2 or 3 requests sent directly to me every week). FTP: We made everything we could available by anonymous FTP at Rice; eventually other sites picked up some of it as well. This included the various drafts of the language spec; any other handouts from the meetings; supporting (sometimes critical) commentary; papers on Fortran D, Vienna Fortran, ADAPT, and other systems; archived email traffic; and the minutes of the meetings. Generally, I put up a couple versions of any document (particularly text formatting stuff) - TeX or LaTeX, Postscript, and compressed versions of large files. This was important, since I've found out some fascinating things about portability (or lack thereof) of different formats. (Hints: keep all lines 80 characters or less; no fancy macros in TeX; at most one "." in a file name (filename.tex.Z doesn't translate well to IBM!); never include ANY pathname.) Minutes: Extremely popular, but lots of work. I'm convinced that making them available was a key to HPFF's success. Make them as detailed as possible, particularly including counts of the votes taken, major topics discussed, and lists of people (humor helps occasionally, too). "Executive Summary" sections with the major issues at the front seemed to be popular. I also used the minutes to announce additions to the FTP archives. Advertizing: Announcements of major news (new drafts, etc.) went everywhere I could think of. This includes the "world" mailing list; newsgroups comp.lang.fortran, comp.lang.misc, and comp.parallel; (indirectly) na-net, scinet, and hpcwire. Meeting minutes went to the world and core mailing lists and the newsgroups. I've been writing short "What is HPF" articles constantly, and I think the same is true of others. Ken, Dave Loveman, Guy, and I have all given large numbers of talks on HPF; again, the same is probably true of others. This includes invited talks at conferences and visits to various companies. From chk@cs.rice.edu Mon Nov 23 15:45:48 1992 Return-Path: Received: from cs.rice.edu by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA26184; Mon, 23 Nov 92 15:45:39 -0500 Received: from DialupEudora (charon.rice.edu) by cs.rice.edu (AA22750); Mon, 23 Nov 92 14:44:21 CST Message-Id: <9211232044.AA22750@cs.rice.edu> Date: Mon, 23 Nov 1992 14:47:55 -0600 To: dongarra@cs.utk.edu From: chk@cs.rice.edu Subject: HPFF organization X-Attachments: :Macintosh HD:4227:HPFF rules: Status: RO Here it is. If anything is unclear, just ask me or (for logistical details) Theresa Chatman (tlc@cs.rice.edu). Chuck HPFF Working Procedures HPFF never had an explicit vote on adopting any operating procedures. We did, however, informally adopt the following rules. General Organization Most of the technical details were hammered out in subgroups, which made the base proposals. The main group would discuss these proposals and (usually) adopt them. In practice, lots of the technical discussions were done on email lists. Keeping those lists public was a big part of the openness of the forum. For a while, each subgroup brought its own proposal as handouts. Eventually, we ended up with a unified draft thanks to Dave Loveman. The intent (which we never lived up to) was that all proposals discussed at a meeting would be in that draft. Despite always having a loose proposal or two, the draft was extremely useful - among other things, it made editing a final report possible. Main Group / Plenary Session Matters For running discussions, we used loosely-enforced Robert's Rules of Order. Basically, we didn't stand on formalities unless the discussion was becoming unruly. Some of the more often-invoked rules: 1. Moving and voting on amendments before the main proposal. Basically, this kept the discussions focussed. 2. Motions coming out of committee (subgroup) are automatically seconded; others need a second from the floor. 3. Triply-nested amendments are not allowed. This keeps the confusion down. Generally, whoever was making the presentation ran the discussion, recognized comments from the floor, etc. Ken usually came in after the meat of the discussion to run the votes. Peer pressure was fairly effective at keeping people from filibustering (I think once there was a call to limit discussion). More common was lots of people wanting to make comments - this was handled by the presenters, usually by saying "OK, let's go clockwise around the table". Organizations were limited to 2 attendees each (not enforced, but no major problems). We passed around an attendence sheet at each meeting to keep track of who was there; because of various planning problems, I recommend using a pre-registration scheme ("send email to xxx@yyy if you plan to attend"). Organizations were asked to commit to having the same attendee at every meeting, and this was generally followed. It's very important to have this kind of continuity in attendees, else we would have spent too much time in remedial education. Each organization (school, company, lab) got one vote - note this was on an organization basis, not a person. We didn't have trouble with cheating on this rule - just make sure the representatives from an organization have agreed on who is voting. An organization was eligible to vote if it had attended 2 of the last 3 meetings, counting the current meeting (i.e. you could attend every other meeting and still vote; you could not vote at your first meeting). Obviously, we couldn't enforce this rule at the first two meetings. Accepting a section of the HPF language spec was a multi-step process. 1. Someone wrote a draft specification; often there were a couple drafts. Details of these were hashed out in the subgroup. 2. First Reading: The subgroup leader (or occasionally the draft author) presented the subgroup-approved draft to the main group. When there was controversy, it was usually pointed out. The main group discussed, suggested changes (sometimes), and held a series of "straw votes" on the proposal. All attendees were eligible to vote in straw votes, which were not binding on the subgroups. 3. More subgroup discussion, both electronic and in person at the next meeting, producing a revised proposal. 4. Second Reading: The subgroup leader presented the revised proposal to the main group. Sections that were substantially the same as the original (or an alternative presented at the first reading) were amended by motion and eventually voted on. Eligibility for votes was as explained above. Major additions (for example, when PURE functions were added to FORALL between meetings) were treated as first readings at this point. Often most of the proposal was accepted, and a few sections were sent back to subgroup for more work; these came back as second readings at the next meeting. 5. Once a section was accepted at second reading, it was "frozen" until the end of the HPFF process. Revisions were only allowed for clarity or when new information surfaced (like discovering that the draft was self-contradictory). This limitation was enforced as strictly as we could, to avoid backtracking. 6. At the end of the process (December), we promised to allow reconsideration of any feature. See also the discussion of the Journal of Development below. Subgroup Matters Subgroups met independently of the main body, usually the afternoon and evening of the day before. The leader of the subgroup ran these meetings using whatever style he or she was comfortable with. Most of us took votes from whoever showed up, and ran a pseud-democratic style. Also, there was a mailing list for each subgroup where most of the discussions went on. Each subgroup was devoted to one topic from the following list: Data distribution FORALL and other parallel statements Fortran 90, storage & sequence association, and the HPF subset Intrinsic functions Parallel I/O EXTRINSIC (nee LOCAL, nee FOREIGN) functions The groups met in parallel, which caused a little friction but was logstically unavoidable. When a subject straddled two groups (like intrinsic functions for enquiring about distributions), the subgroup leaders would talk to each other and decide who would handle it - this often led to minor anti-turf battles (also known as "after you" deadlock). Both groups would act as sanity checks on the results. When it came time to write the draft, each subgroup became a chapter. The subgroup leader was the editor (and usually major author) of the chapter, and was responsible for making sure the chapter reflected the decisions made in the subgroup and in committee. Logistical Matters Meetings were 2.5 days, starting Wednesday afternoon, in Dallas (there were exceptions to this for logistical reasons, but we would have prefered to keep them all on this schedule). A typical schedule was Wednesday 1:30-6:00 Subgroup meetings, about 3 going on in parallel (reserve 4 "breakout" rooms with the hotel, fo 10-20 people each) 6:00-7:30 Unofficial dinner break (usually the subgroup leaders ate together & planned the meeting agenda) 7:30-10:30 More subgroup meetings (subgroup leaders usually ended up staying up late to revise drafts) Thursday 9:00-12:00 Full group meeting (coffee breaks at natural breaks) 12:00-1:30 Lunch (provided) 1:30-6:00 Full group meeting (and coffee breaks) 6:00-8:00 Dinner (attendees pay, but hotel provided transport to area restaurant) 8:00-10:00 (Sometimes) Full group meeting (when no full meeting, subgroups usually met instead) Friday 9:00-12:00 Full group meeting (and coffee breaks) 12:00-1:30 (Sometimes) Lunch (provided if we thought the meeting would last long) 1:30-3:00 (Sometimes) Full group meeting We tried to finish as early as possible on Friday, to allow people to catch flights. Since we scheduled all the meetings early on, we set up a contract with the hotel. I didn't handle the details, but I think this saved us a little money and a lot of aggravation (talk to Theresa Chatman if you need more info). At any rate, this is a great thing for someone on your staff to set up. We financed the meetings primarily from a per-meeting fee of $95 ($75 if we didn't have lunch the second day) per attendee. Ken offered to foot the bill for academics to attend, based on the expectation of NSF funds. We're still waiting on those funds; highly recommend that you don't make such offers without first getting the cash. Documentation The Draft: The earlier you have one the better. David Loveman served as our general editor, collecting the chapters and trying to smooth format details. I contributed the introduction and credits, mainly cribbed from meeting notes and other announcements. Guy Steele contributed a set of macros for BNF syntax and reproducing code segments. We tried to find some formatting from an ANSI standard, but no dice. Toward the end of the process, version control became a problem. We (tried to) set up the following framework: 1. David had the "official" version of the draft. He set deadlines for receiving the chapters, and edited for formatting. 2. David sent me the whole document when all the chapters were done. I LaTeXed it to check for system dependences (never a problem) 3. I sent the document to the "core" mail group (see below), put it out for anonymous FTP, and announced it on the net. 4. Any further changes were supposed to be made to David's edited copy, not the original version (this to make the next round of edits easier). The system worked pretty well, until the final draft when the wrong version of Chapter 6 got distributed... Each subgroup wrote one chapter, generally written and/or edited by the subgroup leader. While the meetings were going on, the draft contained all proposals still under consideration (Guy provided a "\alternative" macro that marked sections as being alternatives to each other). Also, the author of each section was identified in a footnote at the beginning of the section, along with the date (and occasionally other version information). In the current draft, we've moved summaries of some discarded proposals to the "Journal of Development" (primarily the ones dropped for lack of time). All proposals exist in the archives; we may put together a "rationale" document to explain some of the more controversial decisions. We're also planning to move the authorship information from footnotes to the credits chapter in the December draft. It's too early to know how this organization will work for the reader, but the modularity has helped in writing the document. Other lessons from the draft: 1. Make sure the chapter authors realize they are writing a draft chapter, not a stand-alone document. 2. Make sure the person in charge of the credits chapter has plenty of time to work on it (I spent 50% of my time for a week appeasing various corporate egos, wording things right, and checking spelling of names). 3. Proofread the document before sending it out - both spell checking and careful chapter reading. Mailing lists: Every subgroup had its own mailing list. Those lists are where most of the technical action happened; they were very high-volume (final total was something like 1.5Mb of archived messages). On top of that, there was a list for everybody in the world interested in HPF, and another for the "core" group. The "everybody" list was used for the meeting minutes and a few miscellaneous announcements. The core group list was primarily for the meeting attendees, but a few others were also on it for political and/or practical reasons (for example, Gil Weigand and Theresa Chatman were both on the list); it got meeting details, and copies of the various proposals before the meetings. All lists were kept at cs.rice.edu (there were a couple smaller lists other places, including a European list at GMD and several local lists for particular campuses). People could add or delete themselves to/from any of the lists by mailing to another mail alias at Rice. Automating this was a huge win (although I got 2 or 3 requests sent directly to me every week). FTP: We made everything we could available by anonymous FTP at Rice; eventually other sites picked up some of it as well. This included the various drafts of the language spec; any other handouts from the meetings; supporting (sometimes critical) commentary; papers on Fortran D, Vienna Fortran, ADAPT, and other systems; archived email traffic; and the minutes of the meetings. Generally, I put up a couple versions of any document (particularly text formatting stuff) - TeX or LaTeX, Postscript, and compressed versions of large files. This was important, since I've found out some fascinating things about portability (or lack thereof) of different formats. (Hints: keep all lines 80 characters or less; no fancy macros in TeX; at most one "." in a file name (filename.tex.Z doesn't translate well to IBM!); never include ANY pathname.) Minutes: Extremely popular, but lots of work. I'm convinced that making them available was a key to HPFF's success. Make them as detailed as possible, particularly including counts of the votes taken, major topics discussed, and lists of people (humor helps occasionally, too). "Executive Summary" sections with the major issues at the front seemed to be popular. I also used the minutes to announce additions to the FTP archives. Advertizing: Announcements of major news (new drafts, etc.) went everywhere I could think of. This includes the "world" mailing list; newsgroups comp.lang.fortran, comp.lang.misc, and comp.parallel; (indirectly) na-net, scinet, and hpcwire. Meeting minutes went to the world and core mailing lists and the newsgroups. I've been writing short "What is HPF" articles constantly, and I think the same is true of others. Ken, Dave Loveman, Guy, and I have all given large numbers of talks on HPF; again, the same is probably true of others. This includes invited talks at conferences and visits to various companies. From owner-mpi-comm@CS.UTK.EDU Tue Nov 24 18:09:18 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA08323; Tue, 24 Nov 92 18:09:18 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA22602; Tue, 24 Nov 92 17:43:42 -0500 Received: from relay2.UU.NET by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA22596; Tue, 24 Nov 92 17:43:35 -0500 Received: from uunet.uu.net (via LOCALHOST.UU.NET) by relay2.UU.NET with SMTP (5.61/UUNET-internet-primary) id AA11950; Tue, 24 Nov 92 17:43:40 -0500 Received: from kailand.UUCP by uunet.uu.net with UUCP/RMAIL (queueing-rmail) id 174208.17287; Tue, 24 Nov 1992 17:42:08 EST Received: from brisk.kai.com (brisk) by kailand.kai.com via SMTP (5.65d-92031301) id AA07130; Tue, 24 Nov 1992 16:14:37 -0600 Received: by brisk.kai.com (920330.SGI-92101201) id AA06815; Tue, 24 Nov 92 16:14:36 -0600 Date: Tue, 24 Nov 92 16:14:36 -0600 Message-Id: <9211242214.AA06815@brisk.kai.com> To: dongarra@cs.utk.edu Cc: mpi-comm@cs.utk.edu In-Reply-To: Jack Dongarra's message of Tue, 24 Nov 92 15:04:05 -0500 <9211242004.AA20345@thud.cs.utk.edu> Subject: more on the intro From: Steven Ericsson Zenith Sender: zenith@kai.com Organization: Kuck and Associates, Inc. 1906 Fox Drive, Champaign IL USA 61820-7334, voice 217-356-2288, fax 217-356-5199 Concerning the introduction: "The paradigm will not be made obsolete by architectures combining the shared- and distributed-memory views, or by increases in network speeds." I think this sentence is unnecessarily defensive. I'd delete the sentence and the following "thus". I earlier raised an objection to \item A simple way to create processes for the SPMD model there seems to be some redundancy here with \item Process groups The former is a subset of the latter. I'll repeat my noncirculated comments: I would rather not see us say too much about the process model at this stage; except to say that there is some process model defined by the language using the standard and to say something about side effects between processes that affect the message passing semantics (i.e., that there should be none). That does, of course, leave us with some interesting problems for identifying our communication; traditionally a difficult subject in message passing (hence my distribution of this message to the whole committee). The easy route would be to have a global name space of shared "channels" each with a communication characteristic [type] (e.g., "point-to-point" or "one-to-many"): a compiler can check correct usage if we identify the right rules (e.g. a synchronized unidirectional point-to-point communication is shared by only two processes). Such logical naming would map well across all the existing systems and avoid the problems of name servers, processor id, topologies and so forth since any topology can be described by the set of names and its users. Processor ids are, in effect, names in a global name space - and are often channels that have a "many-to-one" characteristic. Steven From owner-mpi-comm@CS.UTK.EDU Sat Nov 28 18:38:03 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA07921; Sat, 28 Nov 92 18:38:03 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA22407; Sat, 28 Nov 92 18:35:38 -0500 Received: from cunyvm.cuny.edu by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA22403; Sat, 28 Nov 92 18:35:36 -0500 Message-Id: <9211282335.AA22403@CS.UTK.EDU> Received: from YKTVMV by CUNYVM.CUNY.EDU (IBM VM SMTP V2R2) with BSMTP id 6064; Sat, 28 Nov 92 18:35:01 EST Date: Sat, 28 Nov 92 18:32:55 EST From: "Marc Snir" X-Addr: (914) 945-3204 (862-3204) 28-226 IBM T.J. Watson Research Center P.O. Box 218 Yorktown Heights NY 10598 To: mpi-comm@cs.utk.edu Subject: previously sent postcript file Reply-To: SNIR@watson.ibm.com Contains an outline I want to use for discussing issues in the poin-to-point subcommittee. I send it to the entire committee since it touches many issues related to collective communication and formal definitions. If somebody cannot print postscript and prefers latex, pls let me know. From owner-mpi-comm@CS.UTK.EDU Sat Nov 28 18:40:52 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA07938; Sat, 28 Nov 92 18:40:52 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA22399; Sat, 28 Nov 92 18:33:55 -0500 Received: from cunyvm.cuny.edu by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA22394; Sat, 28 Nov 92 18:33:40 -0500 Message-Id: <9211282333.AA22394@CS.UTK.EDU> Received: from YKTVMV by CUNYVM.CUNY.EDU (IBM VM SMTP V2R2) with BSMTP id 6053; Sat, 28 Nov 92 18:33:04 EST Date: Sat, 28 Nov 92 18:32:22 EST From: "Marc Snir" To: MPI-COMM@CS.UTK.EDU %!PS-Adobe-2.0 %%Creator: dvips 5.47 Copyright 1986-91 Radical Eye Software %%Title: MPIOUTLN.DVI.* %%Pages: 10 1 %%BoundingBox: 0 0 612 792 %%EndComments %%BeginProcSet: texc.pro /TeXDict 250 dict def TeXDict begin /N /def load def /B{bind def}N /S /exch load def /X{S N}B /TR /translate load N /isls false N /vsize 10 N /@rigin{ isls{[0 1 -1 0 0 0]concat}if 72 Resolution div 72 VResolution div neg scale 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b(adv)m(an)o(tage)h(of)f(ha)o(ving)h(a)f(structured)h(name)g (space)f(for)h(pro)q(cesses)g(is)g(that)f(it)h(simpli\014es)75 892 y(com)o(bining)14 b(of)e(distinct)i(parallel)g(co)q(des)f(in)h(a)e(lo)q (osely)i(coupled)g(application:)20 b(Eac)o(h)13 b(functional)h(subset)75 948 y(can)j(use)h(message)f(passing)h(within)g(its)g(con)o(text,)f(with)g(no) h(c)o(hanges)f(in)h(the)f(lo)q(cal)i(co)q(de.)27 b(The)17 b(same)75 1005 y(concern)k(for)f(mo)q(dularit)o(y)h(militates)h(for)e(a)g(structured)g (t)o(yp)q(e)h(space.)36 b(This)21 b(do)q(es)g(not)g(necessarily)75 1061 y(implies)j(or)d(requires)h(a)f(stac)o(k)g(mec)o(hanism)h(for)f (managing)g(groups,)i(or)e(a)g(tree)g(structure)h(among)75 1118 y(groups.)146 1174 y(First,)14 b(t)o(w)o(o)g(remarks:)143 1268 y Fa(\017)23 b Fg(The)c(preexisting)h(group)f Fb(ALL)f Fg(that)g(includes)j(all)f(pro)q(cesses)g(pro)o(vides)f(a)g(global)g(con)o (text.)31 b(If)189 1324 y(all)17 b(comm)o(unications)f(use)h(this)f(con)o 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y(n)o(um)o(b)q(ering)h(and)g(for)f(relativ) o(e)h(t)o(yp)q(e)g(naming.)30 b(I)19 b(b)q(eliev)o(e)h(this)f(simpli\014es)i (the)d(discussion,)j(without)75 1907 y(in)o(tro)q(ducing)13 b(undue)g(restrictions.)20 b(A)12 b(con)o(text)f(for)g(a)h(comm)o(unication)g (op)q(eration)h(can)f(b)q(e)g(established)75 1964 y(in)k(t)o(w)o(o)e(w)o(a)o (ys:)131 2070 y(1.)22 b(The)f(curren)o(t)h(scop)q(e)g(\(curren)o(t)f(group\)) g(of)g(a)g(comm)o(unication)h(op)q(eration)g(is)g(implicit;)27 b(it)21 b(is)189 2126 y(established)16 b(b)o(y)g(the)f(last)g(executed)h(con) o(text)f(con)o(trolling)h(call)g(\()p Fb(MPI)p 1401 2126 V 17 w(PUSHC)e Fg(and)i Fb(MPI)p 1713 2126 V 16 w(POPC)f Fg(in)189 2183 y(the)e(curren)o(t)h(draft\).)k(Th)o(us,)c(an)o(y)f(pro)q(cess)h(n)o(um) o(b)q(er)h(is)f(understo)q(o)q(d)g(to)f(b)q(e)i(relativ)o(e)f(rank)f(in)i (the)189 2239 y(curren)o(t)g(group,)f(and)h(an)o(y)g(t)o(yp)q(e)g(name)g(is)h (understo)q(o)q(d)f(to)g(b)q(e)g(relativ)o(e)h(to)e(curren)o(t)h(group,)g (and)189 2296 y(do)q(es)j(not)f(con\015icts)i(with)f(t)o(yp)q(e)h(names)e (used)i(within)g(other)f(groups.)27 b(Of)18 b(course,)h(the)f(initial)189 2352 y(scop)q(e)d(is)g Fb(ALL)p Fg(,)e(and)i(the)g(system)f(defaults)h(to)f (a)g(\015at)g(name)h(space)g(if)g(scop)q(e)g(setting)f(commands)189 2409 y(are)h(nev)o(er)g(used.)131 2503 y(2.)22 b(The)g(con)o(text)g(of)f(a)h (comm)o(unication)h(op)q(erations)f(need)h(to)f(b)q(e)h(explicitly)i(sp)q (eci\014ed)f(in)f(the)189 2559 y(comm)o(unication)15 b(op)q(eration)f (itself.)21 b(A)14 b(pro)q(cess)h(ma)o(y)e(b)q(elong)j(to)d(sev)o(eral)i (groups)f(at)f(an)o(y)h(p)q(oin)o(t)189 2615 y(in)19 b(time,)g(and)g(ma)o(y)f (use)h(an)o(y)f(of)g(these)h(groups)f(as)g(scop)q(e)h(for)f(a)g(comm)o (unication)h(op)q(eration.)189 2672 y(Again,)14 b(the)f(initial)j(scop)q(e)e Fb(ALL)f Fg(is)h(prede\014ned,)h(and)f(can)g(b)q(e)g(used)g(as)g(a)f(\015at)g (name)h(space.)19 b(\(In)14 b(a)964 2828 y(8)p eop %%Page: 9 9 bop 189 45 a Fg(language)13 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b(of)g(send)g(and)h(receiv)n(e)75 793 y Fd(receiv)n(e)18 b(criteria)75 879 y Fg(Messages)c(are)h(matc)o(hed)g(b)o (y)h(sender)f(and)h(t)o(yp)q(e,)f(where)g(eac)o(h)g(can)h(b)q(e)g(a)e (\\don't)h(care".)146 935 y(Our)f(exp)q(erience)j(is)e(that)f(matc)o(hing)g (b)o(y)g(t)o(yp)q(e)h(only)l(,)g(or)f(disallo)o(wing)i(\\don't)e(care")g(in)h (the)f(sender)75 992 y(\014eld)20 b(signi\014can)o(tly)h(simpli\014es)g(the)e (implemen)o(tation)i({)d(but)h(some)g(users)g(complained)i(ab)q(out)e(suc)o (h)75 1048 y(restriction.)146 1105 y(Also,)c(do)g(w)o(e)g(w)o(an)o(t)f(to)g (b)q(e)i(explicit)i(ab)q(out)d(the)g(don't)g(care)g(v)m(alue,)h(or)e(use)i (named)f(constan)o(ts?)146 1161 y(Opinions?)75 1283 y Fd(Matc)n(hing)20 b(of)f(data)75 1369 y Fg(F)l(or)c(un)o(t)o(yp)q(ed)g(messages)g(the)g (options)h(are)131 1462 y(1.)22 b(Send)16 b(and)f(receiv)o(e)h(bu\013er)f(ha) o(v)o(e)g(same)g(size)131 1556 y(2.)22 b(Receiv)o(e)16 b(bu\013er)g(is)f(no)g (shorter)g(than)g(send)h(bu\013er)131 1650 y(3.)22 b(No)15 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2233 y(ibilit)o(y)18 b(\(e.g.,)d(can)h(t)o(w)o(o)e(real) i(n)o(um)o(b)q(ers)g(b)q(e)h(receiv)o(ed)g(in)o(to)f(a)g(complex)g(n)o(um)o (b)q(er?\))23 b({)16 b(this)g(is)g(probably)75 2289 y(sp)q(eci\014c)h(to)e (eac)o(h)g(language)g(binding.)146 2346 y(Opinions?)75 2489 y Fh(Syn)n(tax)75 2590 y Fg(This)h(ma)o(y)e(b)q(e,)i(of)f(course,)f(a)h(sub)s (ject)g(of)g(endless)i(dispute.)k(A)15 b(few)g(ob)o(vious)g(guidelines:)143 2684 y Fa(\017)23 b Fg(Short,)14 b(mnemonic)i(names)964 2828 y(9)p eop %%Page: 10 10 bop 143 45 a Fa(\017)23 b Fg(Systematic)15 b(naming)h(con)o(v)o(en)o(tion)143 137 y Fa(\017)23 b Fg(Systematic)15 b(ordering)g(of)g(parameters)143 230 y Fa(\017)23 b Fg(Use,)15 b(in)h(languages)g(where)g(this)f(is)h(p)q (ossible,)h(of)e(optional)h(parameters)f(and)h(k)o(eyw)o(ord)e(param-)189 286 y(eters.)143 379 y Fa(\017)23 b Fg(Use,)15 b(in)h(languages)f(where)g (this)h(p)q(ossible,)h(of)d(o)o(v)o(erloading.)146 469 y(I)d(heard)g(in)h 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921 y(Another)21 b(issue)i(is)f (function)g(vs)f(pro)q(cedure)i(call,)h(in)e(F)l(ortran.)38 b(Pro)q(cedure)22 b(calls)h(seem)e(more)75 977 y(natural)15 b(in)h(F)l(ortran,)e(where)h(function)h(in)o(v)o(o)q(cations)g(cannot)f(b)q (e)h(used)g(as)e(statemen)o(ts.)146 1033 y(Opinions?)22 b(Preferences)16 b(for)f(mnemonics?)21 b(Suggestions)16 b(for)e(F77)h(and)g(C?)75 1176 y Fh(Miscelania)75 1277 y Fg(Do)h(w)o(e)g(w)o(an)o(t)g(a)g Fb(TEST)p Fg(,)f(a)i(non)o(blo)q(c)o(king)h Fb(AWAIT)d Fg(op)q(eration?)25 b(\(Alw)o(a)o(ys)16 b(returns;)h(a)f(successful)i(return)75 1334 y(is)e(equiv)m(alen)o(t)h(to)d(a)h(successful)i(return)e(of)g(a)f(blo)q (c)o(king)j Fb(AWAIT)p Fg(\).)146 1390 y(Do)d(w)o(e)h(w)o(an)o(t)f(to)h Fb(AWAIT)f Fg(sev)o(eral)i(messages?)146 1447 y(Do)h(w)o(e)h(w)o(an)o(t)f(a)g Fb(PROBE)h Fg(function)h(\(tells)f(me)g(whic)o(h)h(messages)f(are)g(w)o (aiting)g(to)f(b)q(e)i(receiv)o(ed)g(b)o(y)75 1503 y(me\)?)146 1560 y(Where)12 b(do)h(w)o(e)f(return)h(information)g(on)g(parameters)f(of)g (receiv)o(ed)i(messages)e(suc)o(h)h(as)f(length,)i(and)75 1616 y(t)o(yp)q(e?)24 b(The)16 b(curren)o(t)g(MPI)h(prop)q(osal)f(has)g(length)h (b)q(e)g(the)f(v)m(alue)i(returned)e(b)o(y)h(the)f(receiv)o(e)h(function)75 1673 y(and)d(t)o(yp)q(e)g(returned)h(b)o(y)f(a)f(subsequen)o(t)i(call)g(to)e Fb(MP)p 964 1673 15 2 v 17 w(INFOT)p Fg(.)g(Another)h(natural)g(c)o(hoice)h (w)o(ould)f(seem)h(to)75 1729 y(b)q(e)f(that)f(that)f(length)i(and)g(t)o(yp)q (e)f(are)g(returned)h(b)o(y)f(the)h(len)g(and)g(t)o(yp)q(e)f(parameters)f(of) h(the)h(initial)h(call,)75 1786 y(but)g(this)h(is)g(error)e(prone:)143 1876 y Fa(\017)23 b Fg(The)d(v)m(alues)h(are)e(returned)i(async)o(hronously)f (for)f(non)o(blo)q(c)o(king)j(receiv)o(es.)35 b(The)20 b(user)g(has)g(to)189 1932 y(remem)o(b)q(er)11 b(not)h(to)f(touc)o(h)g(the)h(actual)g(len)g(and)g (t)o(yp)q(e)g(parameters,)f(in)h(addition)h(of)e(not)h(touc)o(hing)189 1989 y(the)j(receiv)o(e)h(bu\013er,)f(un)o(til)h(the)f(op)q(eration)h (completes.)143 2081 y Fa(\017)23 b Fg(A)f(natural)h(implemen)o(tation)h(w)o (ould)f(b)q(e)g(to)f(alw)o(a)o(ys)g(return)g(the)h(length)g(and)g(t)o(yp)q(e) g(of)f(the)189 2138 y(receiv)o(ed)f(messages.)36 b(Ho)o(w)o(ev)o(er,)20 b(most)g(users)g(will)i(assume)f(that)e(the)i(actual)g(len)g(and)g(t)o(yp)q (e)189 2194 y(parameters)14 b(are)h(not)g(up)q(dated)h(when)f(their)h(v)m (alue)h(is)e(not)g(\\don't)f(care".)143 2286 y Fa(\017)23 b Fg(The)13 b(user)h(will)h(not)e(b)q(e)h(able)g(to)f(use)h(constan)o(ts)e(as)h (actual)h(\\don't)f(care")g(parameter)f(v)m(alues)j(\(or)189 2343 y(an)o(ytime,)g(if)g(the)g(\\natural")g(implemen)o(tation)i(is)e(allo)o (w)o(ed\))143 2435 y Fa(\017)23 b Fg(This)17 b(c)o(hoice)h(b)q(ecomes)g(ev)o (en)f(less)h(app)q(etizing)h(when)e(a)g(handle)h(is)g(reused;)g(then)g(the)f (len)h(and)189 2492 y(t)o(yp)q(e)d(v)m(ariables)h(w)o(ould)g(b)q(e)g(reused,) f(to)q(o.)75 2582 y(It)g(seems)g(safer)f(to)g(return)h(these)g(v)m(alues)h (with)f(the)g(call)g(that)g(concludes)h(the)f(execution)h(of)e(sub)q(op)q (er-)75 2638 y(ation)h(3)g({)g(but)g(w)o(e)g(need)h(to)f(think)h(syn)o(tax.) 146 2695 y(Opinions?)952 2828 y(10)p eop %%Trailer end userdict /end-hook known{end-hook}if %%EOF From owner-mpi-comm@CS.UTK.EDU Mon Nov 30 18:08:53 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA22099; Mon, 30 Nov 92 18:08:53 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA03436; Mon, 30 Nov 92 17:54:53 -0500 Received: from THUD.CS.UTK.EDU by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA03434; Mon, 30 Nov 92 17:54:51 -0500 From: Jack Dongarra Received: by thud.cs.utk.edu (5.61++/2.7c-UTK) id AA26470; Mon, 30 Nov 92 17:54:50 -0500 Date: Mon, 30 Nov 92 17:54:50 -0500 Message-Id: <9211302254.AA26470@thud.cs.utk.edu> To: mpi-comm@cs.utk.edu Subject: draft of introduction Enclosed is a draft the introduction subcommittee has put together. We would like to get your comments and input. We feel that it is in a partial state and will be expanded. Hopefully this draft will help keep the discussion of goals, target, audience, etc. from becoming fragmented in each subcommittee. Jack \section{Introduction} \label{sec:intro} \subsection{Overview and Goals} Message passing is a paradigm used widely on certain classes of parallel machines; especially those with distributed memory. Although there are many variations, the basic concept of processes communicating through messages is well understood. Over the last ten years, substantial progress has been made in casting significant applications in this paradigm. Each vendor has implemented their own variant. More recently, several systems \cite{need references} have demonstrated that a message passing system can be efficiently and be portably implemented. It is thus an appropriate time to try to define both the syntax and semantics of a core of library routines that will be useful to a wide range of users and efficiently implementable on a wide range of computers. In designing MPI we have sought to make use of the most attractive features of a number of existing message passing systems, rather than selecting one of them and adopting it as the standard. Thus, MPI has been strongly influenced by work at the IBM T. J. Watson Research Center by Bala, Kipnis, Snir and colleagues \cite{}, Intel's NX/2 \cite{}, Express \cite{}, nCUBE's Vertex \cite{}, and PARMACS \cite{}. Other important contributions have come from Zipcode \cite{}, Chimp \cite{}, PVM \cite{}, and PICL \cite{}. One of the objectives of this paper is to promote a discussion within the concurrent computing research community of the issues that must be addressed in establishing a practical, portable, and flexible standard for message passing. This cooperative process began with a workshop on standards for message passing held in April 1992 \cite{}. The main advantages of establishing a message passing standard are portability and ease-of-use. In a distributed memory communication environment in which the higher level routines and/or abstractions are build upon lower level message passing routines the benefits of standardization are particularly apparent. Furthermore, the definition of a message passing standard, such as that proposed here, provides vendors with a clearly defined base set of routines that they can implement efficiently, or in some cases provide hardware support for, thereby enhancing scalability. The goal of the Message Passing Interface simply stated is to develop a \it{de facto} standard for writing message-passing programs. As such the interface should establishing a practical, portable, efficient, and flexible standard for message passing. \subsection{Who Should Use This Standard?} This standard is intended for use by all those who want to write portable message-passing programs in Fortran 77 and/or C. This includes individual application programmers, developers software designed to run on parallel machines, and creators of higher-level programming languages, environments, and tools. In order to be attractive to this wide audience, the standard must provide a simple, easy-to-use interface for the basic user while not semantically precluding the high-performance message-passing operations available on advanced machines. \subsection{What Platforms Are Targets For Implementation?} The attractiveness of the message-passing paradigm at least partially stems from its wide portability. Programs expressed this way can run efficiently on distributed-memory multiprocessors, networks of workstations, and combinations of all of these. In addition, shared-memory implementations are possible. The paradigm will not be made obsolete by architectures combining the shared- and distributed-memory views, or by increases in network speeds. It thus should be both possible and useful to implement this standard on a great variety of machines, including those "machines" consisting of collections of other machines, parallel or not, connected by a communication network. \subsection{What Is Included In The Standard?} The standard includes (this is temporarily as inclusive as possible): \begin{itemize} \item Point-to-point communication in a variety of modes, including modes that allow fast communication and heterogeneous communication \item Collective operations \item Process groups \item Communication contexts \item A simple way to create processes for the SPMD model \item Bindings for both Fortran and C \item A model implementation \item A formal specification. \end{itemize} \subsection{What Is Not Included In The Standard?} The standard does not specify: \begin{itemize} \item Explicit shared-memory operations \item Operations that require more operating system support than is currently standard; for example, interrupt-driven receives, remote execution, or active messages \item Program construction tools \item Debugging facilities \item Tracing facilities \end{itemize} Features that are not included can always be offered as extensions by specific implementations. From owner-mpi-comm@CS.UTK.EDU Tue Dec 1 16:39:05 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA17944; Tue, 1 Dec 92 16:39:05 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA27367; Tue, 1 Dec 92 16:14:27 -0500 Received: from relay2.UU.NET by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA27363; Tue, 1 Dec 92 16:14:24 -0500 Received: from uunet.uu.net (via LOCALHOST.UU.NET) by relay2.UU.NET with SMTP (5.61/UUNET-internet-primary) id AA00550; Tue, 1 Dec 92 16:14:28 -0500 Received: from kailand.UUCP by uunet.uu.net with UUCP/RMAIL (queueing-rmail) id 161350.23711; Tue, 1 Dec 1992 16:13:50 EST Received: from brisk.kai.com (brisk) by kailand.kai.com via SMTP (5.65d-92031301 for ) id AA22501; Tue, 1 Dec 1992 15:07:53 -0600 Received: by brisk.kai.com (920330.SGI-92101201) id AA16316; Tue, 1 Dec 92 15:07:51 -0600 Date: Tue, 1 Dec 92 15:07:51 -0600 Message-Id: <9212012107.AA16316@brisk.kai.com> To: mpi-comm@cs.utk.edu Subject: A proposal. From: Steven Ericsson Zenith Sender: zenith@kai.com Organization: Kuck and Associates, Inc. 1906 Fox Drive, Champaign IL USA 61820-7334, voice 217-356-2288, fax 217-356-5199 I've seen several proposals and made a few suggestions myself. I have now had a chance to look at Gropp and Lusk's Manual for the test implementation and I like it as a starting point. I propose to all subcommittees that we use this document as the focus for discussion along with the introduction Jack sent around yesterday. This shouldn't be taken as an endorsement by me of the Gropp and Lusk manual - I have several remarks I would like to make at a later stage. However, it is clear that we need a well considered and simple starting point and I see that in this document plus the introduction. Do I have any seconders? In the HPFF committe structure description we received a few days ago it was noted that much success came from someone taking charge of the central document. I implore someone to do this (Jack?). Steven P.S. I am not ignoring the other comments made in the committees - I think they too can - after debate - be folded into the suggested starting point. From owner-mpi-comm@CS.UTK.EDU Tue Dec 1 19:08:43 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA21233; Tue, 1 Dec 92 19:08:43 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA01862; Tue, 1 Dec 92 18:43:11 -0500 Received: from cunyvm.cuny.edu by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA01858; Tue, 1 Dec 92 18:43:08 -0500 Message-Id: <9212012343.AA01858@CS.UTK.EDU> Received: from YKTVMV by CUNYVM.CUNY.EDU (IBM VM SMTP V2R2) with BSMTP id 7311; Tue, 01 Dec 92 18:42:33 EST Date: Tue, 1 Dec 92 18:43:02 EST From: "Marc Snir" X-Addr: (914) 945-3204 (862-3204) 28-226 IBM T.J. Watson Research Center P.O. Box 218 Yorktown Heights NY 10598 To: mpi-comm@cs.utk.edu Subject: HPF process Reply-To: SNIR@watson.ibm.com The HPF process did not start with a central document. Various peoples wrote proposals for various parts of the language design and, after several iterations, when the number of proposals starting being reasonable and these proposals started being coherent, they were collated into one document that evolved (mostly by successive pruning) into a draft. I suppose we can follow the same approach -- with the initial MPI Draft being our first frame of reference. From owner-mpi-comm@CS.UTK.EDU Fri Dec 4 16:10:12 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA06597; Fri, 4 Dec 92 16:10:12 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA27740; Fri, 4 Dec 92 15:56:38 -0500 Received: from THUD.CS.UTK.EDU by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA27738; Fri, 4 Dec 92 15:56:36 -0500 From: Jack Dongarra Received: by thud.cs.utk.edu (5.61++/2.7c-UTK) id AA07974; Fri, 4 Dec 92 15:56:35 -0500 Date: Fri, 4 Dec 92 15:56:35 -0500 Message-Id: <9212042056.AA07974@thud.cs.utk.edu> To: mpi-comm@cs.utk.edu Subject: addresses for mpi I'm trying to put together a complete mailing list for MPI. Can you fill in the following information and send it to me. Thanks, Jack Name: Address: Email: Fax: Office phone number: Home phone number: (I'll use this only in an emergency and won't circulate.) From owner-mpi-comm@CS.UTK.EDU Mon Dec 7 21:39:33 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA10542; Mon, 7 Dec 92 21:39:33 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA29754; Mon, 7 Dec 92 21:28:26 -0500 Received: from vnet.ibm.com by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA29750; Mon, 7 Dec 92 21:28:21 -0500 Message-Id: <9212080228.AA29750@CS.UTK.EDU> Received: from AUSVM6 by vnet.ibm.com (IBM VM SMTP V2R2) with BSMTP id 3637; Mon, 07 Dec 92 21:26:25 EST Date: Mon, 7 Dec 92 14:02:48 CST From: panda@vnet.ibm.com To: mpi-comm@cs.utk.edu To: mpi-comm@cs.utk.edu Subject: addresses for mpi I'm trying to put together a complete mailing list for MPI. Can you fill in the following information and send it to me. Thanks, Jack NAME: RAJ PANDA ADDRESS: E39/4305 IBM, 11400 BURNET RD., AUSTIN, TX 78758 EMAIL: PANDA@VNET.IBM.COM FAX: 1-512-823-6144 OFFICE PHONE NUMBER: 1-512-838-6632 HOME PHONE NUMBER: 1-512-835-1959 e.) From owner-mpi-comm@CS.UTK.EDU Mon Dec 7 22:10:17 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA10659; Mon, 7 Dec 92 22:10:17 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA29855; Mon, 7 Dec 92 21:41:36 -0500 Received: from vnet.ibm.com by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA29851; Mon, 7 Dec 92 21:41:26 -0500 Message-Id: <9212080241.AA29851@CS.UTK.EDU> Received: from AUSVM6 by vnet.ibm.com (IBM VM SMTP V2R2) with BSMTP id 4638; Mon, 07 Dec 92 21:39:36 EST Date: Mon, 7 Dec 92 14:51:31 CST From: LBWARD@AUSVM6.VNET.IBM.COM To: mpi-comm@cs.utk.edu Subject: address for mpi mailing list Please add my name to the MPI forum. Linton Ward Name: Linton Ward Address: 11400 Burnet Rd, Austin TX 78758 Email: lbward@ausvm6.vmnet.ibm.com Fax: (512) 823-6144 Office phone number: (512) 838-5116 Home phone number: (512) 244-1949 From owner-mpi-comm@CS.UTK.EDU Thu Dec 10 13:10:06 1992 Received: from CS.UTK.EDU by surfer.EPM.ORNL.GOV (5.61/1.34) id AA08984; Thu, 10 Dec 92 13:10:06 -0500 Received: by CS.UTK.EDU (5.61++/2.8s-UTK) id AA18058; Thu, 10 Dec 92 12:47:20 -0500 Received: from THUD.CS.UTK.EDU by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA18051; Thu, 10 Dec 92 12:47:17 -0500 From: Jack Dongarra Received: by thud.cs.utk.edu (5.61++/2.7c-UTK) id AA27178; Thu, 10 Dec 92 12:47:15 -0500 Date: Thu, 10 Dec 92 12:47:15 -0500 Message-Id: <9212101747.AA27178@thud.cs.utk.edu> To: mpi-comm@cs.utk.edu Subject: Information on the MPI meeting Here are some details on the MPI meeting which is set for January 6th-8th 1993 in Dallas. The meeting site will be the: Bristol Suites 7800 Alpha Road Dallas, TX 214-233-7600 The room rate is $89.00. When making a reservation tell them you are with the MPI meeting. TBS Shuttle Service will be providing complimentary shuttle service to and from the airports. If you fly into DFW, use their courtesy telephone and dial 03. If you fly into Love Field, you'll have to use a pay phone. They can be reached at 817-267-5150. Upon boarding the shuttle, refer to the MPI meeting. The registration fee for the meeting will be $75. Please make checks and POs payable to University of Tennessee. We will collect this at the meeting. The registration fee will go for coffee breaks, meeting rooms, AV and printer rentals. We should plan to start at 1:00 pm January 6th and finishing about noon on January 8th. The format of the meeting is: Wednesday, January 6 1:00 pm to 8:00 pm 2 Breakouts for 10 people 1 Breakout for 20 people 5:00 pm to 6:00 pm--On our own for dinner. Thursday, January 7 8:00 am to 10:00 pm 1 U-shape room for 40 people 6:00 pm to 8:00 pm-- The group dinner somewhere in the area. The hotel will provide round trip van transportation. Friday, January 8 8:00 am to 12:00 pm 1 U-shape room for 40 people This is an open meeting and all are welcome. For future planning here is a tentative list of dates, roughly 6 weeks apart, for the series of meetings: January 6-8 February 24-26 April 7-9 May 19-21 June 30-July2 If you have any questions, please feel free to contact me. Jack From owner-mpi-comm@CS.UTK.EDU Wed Dec 23 16:46:29 1992 Received: from convex.convex.com by mozart.convex.com (5.64/1.28) id AA20114; Wed, 23 Dec 92 16:46:25 -0600 Received: from CS.UTK.EDU by convex.convex.com (5.64/1.35) id AA05394; Wed, 23 Dec 92 16:46:20 -0600 Received: from localhost by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA14697; Wed, 23 Dec 92 17:31:12 -0500 X-Resent-To: mpi-comm@CS.UTK.EDU ; Wed, 23 Dec 1992 22:31:10 GMT Errors-To: owner-mpi-comm@CS.UTK.EDU Received: from rios2.EPM.ORNL.GOV by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA14687; Wed, 23 Dec 92 17:31:08 -0500 Received: by rios2.epm.ornl.gov (AIX 3.2/UCB 5.64/4.03) id AA19206; Wed, 23 Dec 1992 17:29:47 -0500 Date: Wed, 23 Dec 1992 17:29:47 -0500 From: walker@rios2.epm.ornl.gov (David Walker) Message-Id: <9212232229.AA19206@rios2.epm.ornl.gov> To: abmacca@cs.sandia.gov, benson@rdvax.enet.dec.com, mpi-comm@cs.utk.edu, peter@sun.math.usfca.edu, srwheat@cs.sandia.gov Subject: MPI Information Status: RO Dear MPI committee member or observer, I need to know how many people to expect at the Dallas so please let me know if you intend to show up by sending email to walker@msr.epm.ornl.gov Please find below s