On Thu, Oct 21, 2010 at 04:53:30PM -0500, Dan Nelson wrote: > ... > An observation: on 8.1, both user and sys times are less, but real time is > higher. So 8.1 finished the build using less CPU, but spent more time > waiting for something else.
Interesting; thanks for pointing that out. > Disk? Network? I don't suppose the machines > are low enough on RAM that you end up swapping at any point? They have 6GB RAM each, but we're running FreeBSD/i386 without PAE. Still, the workloads under test were the only things running (other than fairly constant administrivia) on each of them, and the build is not especially memory-constrained, as far I as I know. As far as disk, during the (vast) majority of the execution time, disk I/O occurs at such a low rate that it's barely noticeable. And these were local builds -- that is, done on local disk (vs. NFS). The captive build tools were accessed via NFS, but that part is the same on each machine. I've attached a file that shows some of the additional rusage fields from /usr/bin/time -- it's fairly wide (240 chars) -- that may provide some additional insight. Some of the differences I note: * maxrss is almost identical (but slightly higher for 8.1 vs. 7.1). * avgsms for 8.1 is small in each case, but 8.1 is about 20 - 30% of 7.1. * pgrec is a bit lower in 8.1. * pf varies a bit, but looks about the same for each. * sw is 0 for all runs (which is as expected). * bio is noticeably lower in 8.1. * boo is also noticeably lower in 8.1. * msgs is also noticably lower in 8.1. * msgr is just about identical in all cases. * sigr is lower in 8.1. * 8.1's vcsw is about 60% of 7.1's. * 8.1's icsw is about 50% of 7.1's. [Each of the above percentages is an "eyeball estimate," so use an appropriate grain of salt.] > Maybe there > was a change to /usr/bin/make that is causing it to launch jobs slower? We use "captive" versions of make, so the version on the system is a moot point. > Julian's suggestion of booting the 8.1 kernel on the 7.1 OS will definitely > narrow down the list of suspects. I'll see about doing something along those lines, but I doubt it will be all that helpful, actually. -- David H. Wolfskill da...@catwhisker.org Depriving a girl or boy of an opportunity for education is evil. See http://www.catwhisker.org/~david/publickey.gpg for my public key.
start stop real user sys maxrss avgsms pgrec pf sw bio boo msgs msgr sigr vcsw icsw os 1287436357 1287461948 25590.99 81502.22 18115.07 403408 40 1632501960 70091 0 1526450 3948957 52333862 16776 414554 116146505 69359713 FreeBSD 8.1-STABLE i386 1287462797 1287488766 25969.26 81452.14 17920.14 403416 33 1632275106 70921 0 1569112 3992055 52289209 16780 415153 112395968 63795293 FreeBSD 8.1-STABLE i386 1287489641 1287515287 25645.84 81548.40 18256.52 403408 44 1633037428 68757 0 1623321 3939857 52405680 16782 415519 120381724 72994804 FreeBSD 8.1-STABLE i386 1287516151 1287541481 25329.64 81546.23 18294.10 403416 44 1632579746 67606 0 1510313 3932011 52341946 16776 415086 120137651 74621868 FreeBSD 8.1-STABLE i386 1287542355 1287568599 26244.59 81431.47 17902.39 403416 30 1632203678 68433 0 1522405 3959469 52304716 16776 415022 111403586 62745487 FreeBSD 8.1-STABLE i386 1287525363 1287546846 21483.13 82628.20 21703.09 403344 170 1646120708 69576 0 1714249 4096652 66054010 16776 426045 181765163 138243214 FreeBSD 7.1-RELEASE-JNPR-4 i386 1287548005 1287569100 21094.63 82853.19 22185.02 403344 194 1646134922 69189 0 1731574 4130719 66054759 16776 425545 200096792 162326694 FreeBSD 7.1-RELEASE-JNPR-4 i386 1287570300 1287591371 21071.33 82756.81 21943.22 403348 184 1646103669 70720 0 1841404 4097966 66064504 16786 426741 187956827 152273232 FreeBSD 7.1-RELEASE-JNPR-4 i386 1287592592 1287614103 21511.23 82637.30 21849.90 403344 177 1646110915 69878 0 1704692 4088578 66057042 16776 424758 189088692 145093952 FreeBSD 7.1-RELEASE-JNPR-4 i386 1287615323 1287636770 21446.42 82715.81 21708.97 403344 169 1646267475 68996 0 1702403 4096640 66087016 16776 426374 175517603 138999711 FreeBSD 7.1-RELEASE-JNPR-4 i386
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