Re: Time sliced CFQ io scheduler
From: Prakash K. Cheemplavam
Date: Fri Dec 03 2004 - 06:55:33 EST
Jens Axboe schrieb:
On Fri, Dec 03 2004, Prakash K. Cheemplavam wrote:
Jens Axboe schrieb:
On Fri, Dec 03 2004, Prakash K. Cheemplavam wrote:
But at least this patch lets you set slice_sync and slice_async
seperately, if you want to experiement.
An idea, which values I should try?
Just see if the default ones work (or how they work :-)
BTW, I just did my little test on the ide drive and it shows the same
problem, so it is not sata / libata related.
Single read/writer case works fine here for me, about half the bandwidth
for each. Please show some vmstats for this case, too. Right now I'm not
terribly interested in problems with raid alone, as I can poke holes in
that. If the single drive case is correct, then we can focus on raid.
I have not enough space to perform this test on the ide drive, so I did
it on the sata (single disk). The patch doesn't seem to be better. (But
on the other hand I haven't tested you first version on single disk.) At
least it still doesn't look good enough in my eyes.
procs -----------memory---------- ---swap-- -----io---- --system--
----cpu----
r b swpd free buff cache si so bi bo in cs us
sy id wa
1 3 2704 5368 1528 906540 0 4 2176 24068 1245 743 0
7 0 93
0 3 2704 5432 1532 906252 0 0 5072 28160 1277 782 1
8 0 91
0 5 2704 5688 1532 906080 0 0 9280 4524 1309 842 1
10 0 89
1 3 2704 5232 1544 906208 0 0 6404 76388 1285 716 1
14 0 85
0 3 2704 5496 1544 906524 0 0 8328 26624 1301 856 1
8 0 91
0 3 2704 5512 1528 906636 0 0 9484 22016 1302 883 1
8 0 91
0 3 2704 5816 1500 906296 0 0 5508 10288 1270 749 1
9 0 90
0 4 2704 5620 1488 906608 0 0 3076 19920 1267 818 0
13 0 87
1 4 2704 5684 1456 906432 0 0 3204 18432 1252 704 1
8 0 91
1 3 2704 5504 1408 906168 0 0 5252 28672 1279 777 1
14 0 85
0 4 2704 5120 1404 906296 0 0 8968 16384 1351 876 1
9 0 90
0 4 2704 5364 1404 905620 0 0 5252 26112 1339 835 1
14 0 85
0 4 2704 5600 1432 905036 0 0 1468 15876 1312 741 2
8 0 90
1 4 2704 5556 1424 904704 0 0 1664 26112 1243 714 1
10 0 89
0 4 2704 5492 1428 904100 0 0 1412 31232 1253 760 1
15 0 84
0 4 2704 5568 1432 903456 0 0 1668 29696 1253 703 1
14 0 85
1 4 2704 5620 1408 902980 0 0 1280 28672 1248 732 0
14 0 86
0 4 2704 5236 1404 902888 0 0 2180 28704 1252 705 1
11 0 88
0 4 2704 5632 1388 902180 0 0 1536 28160 1251 731 1
11 0 88
0 3 2704 5120 1356 905968 0 0 384 57896 1257 751 1
14 0 85
Try increasing slice_sync and idle, just for fun.
Changed to 150 resp. 6:
procs -----------memory---------- ---swap-- -----io---- --system--
----cpu----
r b swpd free buff cache si so bi bo in cs us
sy id wa
1 5 2704 5720 960 900020 0 0 68 26624 1251 741 1
16 0 83
1 3 2704 5708 1004 900312 0 0 312 4044 1294 686 1
11 0 88
0 1 2704 5484 1024 899800 0 0 396 40008 1236 608 1
5 0 94
0 3 2704 5284 1036 900696 0 0 516 49196 1246 682 1
5 0 94
1 3 2704 5640 1040 900956 0 0 1416 21504 1252 722 1
4 0 95
0 3 2704 5120 1040 902108 0 0 2688 12288 1230 672 1
2 0 97
1 3 2704 5416 1036 902276 0 0 3076 0 1248 632 0
2 0 98
0 4 2704 5448 1092 902748 0 0 11700 16 1306 857 1
16 0 83
0 3 2704 5712 1132 900704 0 0 1064 63488 1259 755 1
15 0 84
0 3 2704 5476 1156 901336 0 0 5656 8296 1272 725 1
7 0 92
0 3 2704 5320 1208 900996 0 0 2988 3972 1256 696 1
18 0 81
1 4 2704 5288 1240 899660 0 0 1956 60964 1278 757 1
12 0 87
0 3 2704 5596 1292 899032 0 0 1688 24732 1284 813 1
8 0 91
0 3 2704 6124 1308 899776 0 0 1424 42496 1253 678 1
7 0 92
1 3 2704 5744 1324 900124 0 0 16 23552 1250 707 1
9 0 90
0 3 2704 5108 1332 900768 0 0 1800 19968 1242 703 1
4 0 95
0 3 2704 5640 1332 900132 0 0 3204 16896 1240 689 1
1 0 98
0 3 2704 5512 1344 900696 0 0 2564 3036 1255 652 1
2 0 97
2 3 2704 5264 1364 901384 0 0 2704 42572 1253 726 1
10 0 89
1 3 2704 5096 1368 898108 0 0 1808 51724 1240 1984 1
53 0 46
procs -----------memory---------- ---swap-- -----io---- --system--
----cpu----
r b swpd free buff cache si so bi bo in cs us
sy id wa
1 4 2704 5572 1348 896164 0 0 2816 18944 1239 1304 1
30 0 69
0 4 2704 5436 1332 896152 0 0 3204 17408 1239 716 0
6 0 94
0 4 2704 5452 1324 895884 0 0 3076 20480 1248 711 2
8 0 90
0 4 2704 5444 1328 895668 0 0 3020 16384 1360 830 1
7 0 92
0 4 2704 5708 1328 895248 0 0 1976 21952 1509 1213 4
8 0 88
0 4 2704 5708 1328 895020 0 0 1536 25200 1258 803 2
10 0 88
0 4 2704 5836 1332 894880 0 0 3204 16264 1281 908 3
8 0 89
0 4 2704 5668 1320 895084 0 0 896 18172 1433 941 1
7 0 92
0 4 2704 5324 1324 895644 0 0 4612 15924 1450 968 1
7 0 92
0 3 2704 5464 1324 897836 0 0 7176 42820 1421 1074 1
29 0 70
1 3 2704 5304 1324 898092 0 0 896 11516 1266 727 1
2 0 97
0 4 2704 5336 1312 898080 0 0 2436 16684 1270 971 1
10 0 89
0 3 2704 5608 1328 897816 0 0 17040 14124 1463 1162 3
7 0 90
0 3 2704 5272 1348 897960 0 0 18196 11264 1435 1281 2
13 0 85
0 3 2704 5592 1348 897488 0 0 6792 24284 1348 1102 6
8 0 86
0 3 2704 5528 1364 897448 0 0 872 19516 1239 760 1
6 0 93
0 3 2704 5592 1364 897348 0 0 1976 22408 1253 761 1
5 0 94
0 3 2704 5528 1364 897252 0 0 2048 30820 1267 858 1
8 0 91
0 3 2704 5528 1372 897132 0 0 5640 18812 1382 907 1
6 0 93
0 3 2704 5208 1368 897388 0 0 2820 17356 1352 863 1
5 0 94
Prakash
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