Date: Wed, 17 Oct 2007 12:11:03 -0400 From: "Josh Carroll" <josh.carroll@gmail.com> To: freebsd-stable@freebsd.org Subject: ULE vs. 4BSD in RELENG_7 Message-ID: <8cb6106e0710170911x77e72e95qb322f51d84a31813@mail.gmail.com>
next in thread | raw e-mail | index | archive | help
All, I mentioned this on another thread, but I think it deserves a separate thread. Not only so it will get its own attention, but also so I don't hijack the other thread. I have noticed some performance discrepancies with ULE and 4BSD in RELENG_7, specifically with ffmpeg. I have all the kernel debugging options disabled, and as I understand it, the userland debugging is all off by default in RELENG_7. That said, I'm seeing 5% better performance from the 4BSD scheduler for ffmpeg -threads 8 on a quad-core Intel desktop setup (Q6600 cpu). I am also comparing as a baseline to RELENG_6_2 (I only have 4BSD scheduler numbers for that, though). Here are the run times for the selected benchmark: RELENG_6_2 (4BSD): 1:32.39 RELENG_7 (4BSD): 1:32.44 RELENG_7 (ULE): 1:37.15 Difference (4BSD vs. ULE on 7): 5.095 % Please see below for "backup data" on this (vmstat 5 output during both a 4BSD and ULE run). As an additional data point, I went ahead and wrote a perl script that forks 4 simultaneous ffmpeg processes (without -threads, obviously). Here are the results (much closer, but still 4BSD is faster): RELENG_7 (4BSD): 7:20.81 RELENG_7 (ULE): 7:22.63 This is only a 1% difference, but 4BSD is still faster. So, am I doing something wrong here? Are there additional kernel options/settings I need to tweak ULE properly? Or is this particular workload simply better on 4BSD? Thanks! Josh vmstat 5 output during ULE/4BSD runs with ffmpeg ... -threads 8: 4BSD: procs memory page disks faults cpu r b w avm fre flt re pi po fr sr ad6 ad8 in sy cs us sy id 1 1 0 412348 1589544 508 0 0 0 507 0 0 0 22 694 643 3 0 97 3 1 0 754860 1416760 8504 0 0 0 20 0 0 0 15 1339 2092 94 1 5 6 1 0 757940 1402456 565 0 0 0 1 0 0 0 18 1081 944 98 0 2 6 1 0 757940 1396564 188 0 0 0 3 0 15 0 45 1136 1075 96 0 4 7 1 0 757940 1393236 30 0 0 0 1 0 1 0 21 937 851 97 0 3 6 2 0 760192 1390756 60 0 0 1 43 0 5 0 25 1065 902 96 0 3 5 2 0 760192 1390304 3 0 0 0 100 0 0 0 19 1365 1240 98 0 2 4 1 0 758964 1388592 25 0 0 0 16 0 0 0 15 997 869 96 0 4 7 1 0 758964 1386132 3 0 0 0 0 0 0 0 14 810 766 96 0 4 5 1 0 758964 1383608 2 0 0 0 0 0 0 0 28 695 713 99 0 1 4 1 0 758964 1380372 26 0 0 0 1 0 7 0 29 806 842 96 0 3 7 1 0 759992 1377440 11 0 0 0 1 0 1 0 29 810 802 98 0 2 3 1 0 759992 1375412 2 0 0 0 2 0 0 0 20 879 785 97 0 3 4 1 0 759992 1373168 1 0 0 0 1 0 0 0 13 1032 876 95 0 5 5 1 0 759992 1371204 2 0 0 0 0 0 0 0 21 1197 984 85 0 15 5 1 0 759992 1367676 3 0 0 0 0 0 0 0 20 1155 897 98 0 1 4 1 0 759992 1362272 24 0 0 0 0 0 0 0 21 826 719 98 0 2 6 2 0 762244 1359028 58 0 0 0 43 0 1 0 23 1404 1071 96 0 4 procs memory page disks faults cpu r b w avm fre flt re pi po fr sr ad6 ad8 in sy cs us sy id 7 2 0 762244 1356036 7 0 0 0 0 0 0 0 21 1236 959 99 0 1 ULE: procs memory page disks faults cpu r b w avm fre flt re pi po fr sr ad6 ad8 in sy cs us sy id 0 4 0 283788 1781208 2333 7 17 0 1633 0 0 0 211 4057 1702 1 1 99 6 2 0 631152 1606120 8180 5 23 0 30 0 65 0 157 915 371336 79 0 21 6 2 0 634228 1583908 906 0 0 0 3 0 5 0 32 566 940216 93 0 7 6 2 0 634228 1575052 227 0 0 0 0 0 1 0 96 915 694291 94 0 6 5 2 0 636276 1569768 54 0 0 0 0 0 1 0 79 722 984529 93 0 7 6 2 0 636276 1565184 3 0 0 0 0 0 0 0 56 749 615641 95 0 5 6 2 0 633024 1560904 182 0 0 0 224 0 15 0 64 892 554573 95 0 5 6 2 0 633024 1557648 1 0 0 0 0 0 0 0 21 1046 925070 94 0 6 8 1 0 631800 1553088 27 0 0 0 16 0 0 0 23 773 421820 96 0 3 7 1 0 631800 1548752 3 0 0 0 0 0 0 0 27 552 714116 96 0 4 7 1 0 631800 1543804 20 0 0 0 0 0 0 0 20 541 887702 94 0 6 6 1 0 632824 1537948 15 0 0 0 1 0 1 0 25 590 691248 95 0 5 7 1 0 632824 1533896 1 0 0 0 4 0 1 0 21 676 545389 95 0 5 7 1 0 632824 1528332 2 0 0 0 0 0 0 0 23 787 637327 93 0 7 5 1 0 632824 1525668 1 0 0 0 0 0 0 0 13 893 722130 90 0 10 3 1 0 632824 1520008 3 0 0 0 0 0 0 0 25 897 1216075 81 0 19 6 1 0 632824 1510980 25 0 0 0 0 0 0 0 33 932 1126821 90 0 10 7 1 0 632824 1503956 1 0 0 0 3 0 0 0 29 804 961332 93 0 7 procs memory page disks faults cpu r b w avm fre flt re pi po fr sr ad6 ad8 in sy cs us sy id 4 2 0 635076 1498816 59 0 0 0 43 0 0 0 24 1014 1188872 91 0 9 7 2 0 635076 1492764 7 0 0 0 0 0 1 0 28 1283 1085336 88 0 11
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?8cb6106e0710170911x77e72e95qb322f51d84a31813>