Re: [OMPI users] mixed versions of openmpi ? (1.4.1 and 1.4.3)
Am 29.10.2010 um 18:47 schrieb Jeff Squyres: > On Oct 29, 2010, at 12:40 PM, Reuti wrote: > >>> I'd have to go check 1.4.3 and 1.4.1 to be sure, but I would generally >>> *NOT* assume that different versions like this are compatible. >> >> I'm getting confused, as these versions are exactly fitting "x.(y+1).*" >> which you mention below. So they should work together by design. > > It depends on what you mean by "work together". > > 1. OMPI provides an ABI guarantee for x.y.* and x.(y+1).*, where y is odd. > So if you compile your MPI app with Open MPI v1.4.1, it'll work just fine > with 1.4.3. (the only disclaimer is that this guarantee started with > v1.3.2). Note that y must be odd -- so if you compile your MPI app with > v1.4.1, it does *not* necessarily work with v1.5. Indeed, we broken ABI > between the v1.3/v1.4 series and the v1.5 series (our ABI guarantee allows us > to do this). Yep, I read it this way in your first reply. > 2. OMPI does *not* provide multi-version *interoperability* guarantees. Say > you compile your MPI app against OMPI v1.4.1. Then you run it across a bunch > of nodes, but some nodes have OMPI v1.4.1 on them and others have OMPI v1.4.3 > (i.e., your app gets libmpi.so from v1.4.1 on some nodes and libmpi.so from > v1.4.3 on other nodes). This is absolutely not guaranteed to work -- we > don't even try to maintain this kind of compatibility. Aha, now I see. When all are the same, it's for sure no problem, but with different ones on different nodes you get a mixture of libraries then of course for one and the same execution. So, when e.g. the protocol for the message which is send to another node changed, it will break. NB: If I would upgrade my cluster in two steps, I would for a short time adjust the queuing system to get nodes for each parallel job where all have the same version then. -- Reuti > > Does that make sense? > > -- > Jeff Squyres > jsquy...@cisco.com > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > > ___ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users
Re: [OMPI users] mixed versions of openmpi ? (1.4.1 and 1.4.3)
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 I guess we will play it safe and upgrade every cluster at once so that we won't get bad surprises. thank you Jeff. On 10/29/2010 06:40 PM, Reuti wrote: > Hi, > > Am 29.10.2010 um 18:27 schrieb Jeff Squyres: > >> I'd have to go check 1.4.3 and 1.4.1 to be sure, but I would generally *NOT* >> assume that different versions like this are compatible. > > I'm getting confused, as these versions are exactly fitting "x.(y+1).*" which > you mention below. So they should work together by design. > > -- Reuti > > >> Open MPI makes an ABI promise (that started with version 1.3.2) that all the >> releases in a given feature series and its corresponding super-stable series >> (i.e., x.y.* and x.(y+1).*, where y is odd) are ABI compatible. But we make >> no guarantees about wire protocols being compatible, or other things like >> that. >> >> So in general, it's "pleasantly surprising" if the different releases work >> together, but I wouldn't rely on it *at all*. :-) >> If I get it well, ABI compatible means something compiled with x.y.* will run on x.y+1.* without the need for you to recompile. mixing x.y and x.y+1 on the same machinefile (and that's what we are talking about) can only work by accident, not by design. >> >> On Oct 29, 2010, at 12:12 PM, guillaume ranquet wrote: >> > Hi list, > I'm sorry to bother you with a stupid question. > > we intend to have for a short period of time, some nodes with 1.4.3 and > others with 1.4.1 (before upgrading everyone to 1.4.3). > > I made various test and found both versions to be running together quite > well with a mixed set of nodes. > > my tests were quite simple, I compiled and ran mpi hello_worlds with > both versions. > It wouldn't be serious for me to assume both versions fully compatible > after these tests -and I must admit I lack the time and technical > knowledge to run further testing. > > has anyone any insight on what have changed that would break compatibility? > I guess nothing, since they are the same major.minor :) > > > regards, > Guillaume Ranquet. >>> ___ users mailing list us...@open-mpi.org http://www.open-mpi.org/mailman/listinfo.cgi/users >> >> >> -- >> Jeff Squyres >> jsquy...@cisco.com >> For corporate legal information go to: >> http://www.cisco.com/web/about/doing_business/legal/cri/ >> >> >> ___ >> users mailing list >> us...@open-mpi.org >> http://www.open-mpi.org/mailman/listinfo.cgi/users > ___ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.16 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJMyvxLAAoJEEzIl7PMEAliTnoH/R4GhehUiFZo6eeSh/Rv9KJc ZhAJIRTFH0z7+R2V4ggDyIWFVEv0mktQq/WEqQTbGNyVVvhWVFjCxrI7deZ+FkZS EFv9oIlKM6gNR+cFdoN4xW4ZfiIoCTGddG6XOxLXkZQnhaG30s5UUmIuoBLvgQhb mTq43WdEPpWsSuyMzo48hizT1PFqpPR101ITnIa2y4T5FC5QktJhbp85HbPaNE2Z ej7kwXcgLEnTDk9wF4rZRah8vdIdtxwghwGhytVLqMFBCB4MR8hWMYTakJbIOt/7 GkFtOv0D7hruHhl9dNk+o8VyHMQq6bzlqs3UdQxW1Hx1N2w0ngHK6fzfUnYRVVY= =TsJh -END PGP SIGNATURE- smime.p7s Description: S/MIME Cryptographic Signature
Re: [OMPI users] mixed versions of openmpi ? (1.4.1 and 1.4.3)
On Oct 29, 2010, at 12:40 PM, Reuti wrote: >> I'd have to go check 1.4.3 and 1.4.1 to be sure, but I would generally *NOT* >> assume that different versions like this are compatible. > > I'm getting confused, as these versions are exactly fitting "x.(y+1).*" which > you mention below. So they should work together by design. It depends on what you mean by "work together". 1. OMPI provides an ABI guarantee for x.y.* and x.(y+1).*, where y is odd. So if you compile your MPI app with Open MPI v1.4.1, it'll work just fine with 1.4.3. (the only disclaimer is that this guarantee started with v1.3.2). Note that y must be odd -- so if you compile your MPI app with v1.4.1, it does *not* necessarily work with v1.5. Indeed, we broken ABI between the v1.3/v1.4 series and the v1.5 series (our ABI guarantee allows us to do this). 2. OMPI does *not* provide multi-version *interoperability* guarantees. Say you compile your MPI app against OMPI v1.4.1. Then you run it across a bunch of nodes, but some nodes have OMPI v1.4.1 on them and others have OMPI v1.4.3 (i.e., your app gets libmpi.so from v1.4.1 on some nodes and libmpi.so from v1.4.3 on other nodes). This is absolutely not guaranteed to work -- we don't even try to maintain this kind of compatibility. Does that make sense? -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/
Re: [OMPI users] mixed versions of openmpi ? (1.4.1 and 1.4.3)
Hi, Am 29.10.2010 um 18:27 schrieb Jeff Squyres: > I'd have to go check 1.4.3 and 1.4.1 to be sure, but I would generally *NOT* > assume that different versions like this are compatible. I'm getting confused, as these versions are exactly fitting "x.(y+1).*" which you mention below. So they should work together by design. -- Reuti > Open MPI makes an ABI promise (that started with version 1.3.2) that all the > releases in a given feature series and its corresponding super-stable series > (i.e., x.y.* and x.(y+1).*, where y is odd) are ABI compatible. But we make > no guarantees about wire protocols being compatible, or other things like > that. > > So in general, it's "pleasantly surprising" if the different releases work > together, but I wouldn't rely on it *at all*. :-) > > > On Oct 29, 2010, at 12:12 PM, guillaume ranquet wrote: > >> -BEGIN PGP SIGNED MESSAGE- >> Hash: SHA1 >> >> Hi list, >> I'm sorry to bother you with a stupid question. >> >> we intend to have for a short period of time, some nodes with 1.4.3 and >> others with 1.4.1 (before upgrading everyone to 1.4.3). >> >> I made various test and found both versions to be running together quite >> well with a mixed set of nodes. >> >> my tests were quite simple, I compiled and ran mpi hello_worlds with >> both versions. >> It wouldn't be serious for me to assume both versions fully compatible >> after these tests -and I must admit I lack the time and technical >> knowledge to run further testing. >> >> has anyone any insight on what have changed that would break compatibility? >> I guess nothing, since they are the same major.minor :) >> >> >> regards, >> Guillaume Ranquet. >> -BEGIN PGP SIGNATURE- >> Version: GnuPG v2.0.16 (GNU/Linux) >> Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ >> >> iQEcBAEBAgAGBQJMyvJTAAoJEEzIl7PMEAliT4kH/RY4WXhEO5R8H3DNIWW7Y91z >> 6q4BrymLrBSl7rnnEgALBMiPGK9lQgqEtv9k3xCFbfOfWXIFreIHH8ZFDzt1BjQI >> TZ58SwVE9CIMmESoJ1P52R+WCbKYur3U2eda//1cfnZ28ZYjnKN/xYlT/wv8hqg3 >> GsW+seMR8X+1nNFkH1UQHIBVO2cXaK24BtSe4cvDFaMaUbe0Qlmxg55BbCSYB4ED >> VBbplp/ty0tojmZdJLqSsp7nZ84oCfvAfZf16fJTDHNYhUSvNz/fldnxWrm7WTUb >> VzM94yJf0IHfNAB/YvpXECGFL9cPWeG/F6Bm+r6GSMRvd0MeLbp1HWJTbVYlCwo= >> =NwEP >> -END PGP SIGNATURE- >> >> ___ >> users mailing list >> us...@open-mpi.org >> http://www.open-mpi.org/mailman/listinfo.cgi/users > > > -- > Jeff Squyres > jsquy...@cisco.com > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > > ___ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users
Re: [OMPI users] mixed versions of openmpi ? (1.4.1 and 1.4.3)
I'd have to go check 1.4.3 and 1.4.1 to be sure, but I would generally *NOT* assume that different versions like this are compatible. Open MPI makes an ABI promise (that started with version 1.3.2) that all the releases in a given feature series and its corresponding super-stable series (i.e., x.y.* and x.(y+1).*, where y is odd) are ABI compatible. But we make no guarantees about wire protocols being compatible, or other things like that. So in general, it's "pleasantly surprising" if the different releases work together, but I wouldn't rely on it *at all*. :-) On Oct 29, 2010, at 12:12 PM, guillaume ranquet wrote: > -BEGIN PGP SIGNED MESSAGE- > Hash: SHA1 > > Hi list, > I'm sorry to bother you with a stupid question. > > we intend to have for a short period of time, some nodes with 1.4.3 and > others with 1.4.1 (before upgrading everyone to 1.4.3). > > I made various test and found both versions to be running together quite > well with a mixed set of nodes. > > my tests were quite simple, I compiled and ran mpi hello_worlds with > both versions. > It wouldn't be serious for me to assume both versions fully compatible > after these tests -and I must admit I lack the time and technical > knowledge to run further testing. > > has anyone any insight on what have changed that would break compatibility? > I guess nothing, since they are the same major.minor :) > > > regards, > Guillaume Ranquet. > -BEGIN PGP SIGNATURE- > Version: GnuPG v2.0.16 (GNU/Linux) > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ > > iQEcBAEBAgAGBQJMyvJTAAoJEEzIl7PMEAliT4kH/RY4WXhEO5R8H3DNIWW7Y91z > 6q4BrymLrBSl7rnnEgALBMiPGK9lQgqEtv9k3xCFbfOfWXIFreIHH8ZFDzt1BjQI > TZ58SwVE9CIMmESoJ1P52R+WCbKYur3U2eda//1cfnZ28ZYjnKN/xYlT/wv8hqg3 > GsW+seMR8X+1nNFkH1UQHIBVO2cXaK24BtSe4cvDFaMaUbe0Qlmxg55BbCSYB4ED > VBbplp/ty0tojmZdJLqSsp7nZ84oCfvAfZf16fJTDHNYhUSvNz/fldnxWrm7WTUb > VzM94yJf0IHfNAB/YvpXECGFL9cPWeG/F6Bm+r6GSMRvd0MeLbp1HWJTbVYlCwo= > =NwEP > -END PGP SIGNATURE- > > ___ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/
