Re: 2.6.1 slower than 2.4, smp/scsi/sw-raid/reiserfs

Philip Martin
2004-02-02T19:11:16Z

Nick Piggin <piggin@cyberone.com.au> writes:

> Another thing I just saw - you've got quite a lot of memory in
> buffers which might be something going wrong.
>
> When the build finishes and there is no other activity, can you
> try applying anonymous memory pressure until it starts swapping
> to see if everything gets reclaimed properly?

How do I apply anonymous memory pressure?

> Was each kernel freshly booted and without background activity
> before each compile?

Each kernel was freshly booted. There were a number of daemons
running, and I was running X, but these don't appear to use much
memory or CPU and the network was disconnected. Just after a boot
there is lots of free memory, but in normal operation the machine uses
its memory, so to make it more like normal I ran "find | grep" before
doing the build. Then I ran make clean, make, make clean, make and
took numbers for the second make.

You can have the numbers straight after a boot as well. In this case
I rebooted, logged in, ran make clean and make -j4.

I can hear disk activity on this machine. During a 2.4.24 build the
activity happens in short bursts a few seconds apart. During a 2.6.1
build it sounds as if there is more activity, with each burst of
activity being a little longer. However that just the impression I
get, I haven't tried timing anything, I may be imagining it.

2.4.24
procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu----
r b swpd free buff cache si so bi bo in cs us sy id wa
6 0 0 379328 17100 45608 0 0 16 0 115 466 89 11 0 0
5 0 0 388180 17108 45412 0 0 72 0 113 727 75 25 0 0
4 0 0 376448 17108 45540 0 0 48 0 128 602 82 18 0 0
5 0 0 378692 17112 45824 0 0 44 0 111 477 90 10 0 0
3 3 0 376968 17408 46036 0 0 116 592 146 734 80 20 0 0
4 0 0 383832 17924 47080 0 0 36 1484 295 490 80 11 9 0
5 0 0 388620 17928 46268 0 0 36 0 116 933 71 29 0 0
4 0 0 376864 17928 46360 0 0 52 0 116 659 81 19 0 0
5 0 0 389580 17928 46772 0 0 20 0 115 502 86 14 0 0
4 0 0 382452 17928 46656 0 0 68 0 115 1082 66 34 0 0
5 1 0 384800 17980 47000 0 0 4 108 125 296 94 6 0 0
6 1 0 385140 18484 46956 0 0 76 1088 274 1282 62 38 0 0
6 0 0 381352 18904 47272 0 0 20 1544 221 522 88 12 0 0
4 0 0 381636 18904 47448 0 0 104 0 126 829 75 25 0 0
5 0 0 376732 18904 47408 0 0 32 0 114 727 83 17 0 0
5 0 0 384100 18904 47572 0 0 0 0 108 686 76 24 0 0
5 0 0 378904 18908 47724 0 0 100 0 121 897 71 29 0 0
3 2 0 372608 19344 47960 0 0 56 832 198 319 87 7 5 0
8 0 0 385204 19428 48096 0 0 12 656 199 819 80 19 0 0
4 0 0 374144 19428 48312 0 0 80 0 120 801 71 29 0 0
6 0 0 376628 19428 48604 0 0 32 0 109 512 88 12 0 0
procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu----
r b swpd free buff cache si so bi bo in cs us sy id wa
6 0 0 380208 19428 48836 0 0 32 0 116 777 78 22 0 0
5 0 0 378016 19428 48800 0 0 32 0 114 679 75 25 0 0
4 1 0 376360 20092 49052 0 0 56 1244 282 723 79 21 0 0
4 0 0 379996 20588 48980 0 0 0 1804 307 888 80 20 0 0
4 0 0 372924 20596 49480 0 0 28 0 140 582 82 18 0 0
5 0 0 382632 20596 49260 0 0 20 0 127 946 72 28 0 0
4 0 0 374536 20596 49704 0 0 20 0 128 662 80 20 0 0
6 0 0 383852 20596 49536 0 0 12 0 110 838 79 21 0 0
4 1 0 371160 20888 49572 0 0 20 576 176 768 75 25 0 0
5 0 0 383564 21236 49800 0 0 12 1280 226 803 79 20 0 0
4 0 0 372592 21236 49908 0 0 108 0 120 919 66 34 0 0
5 0 0 367796 21236 50368 0 0 56 0 118 427 90 10 0 0
5 0 0 373172 21244 50344 0 0 72 0 121 714 78 22 0 0
5 0 0 375740 21244 50500 0 0 64 0 110 498 86 14 0 0
3 2 0 371356 21536 50936 0 0 108 584 175 716 79 21 0 0
5 0 0 374716 21900 51324 0 0 24 1436 229 599 86 14 0 0
5 0 0 375416 21900 51236 0 0 48 0 106 826 78 22 0 0
5 0 0 372428 21900 51116 0 0 16 0 111 582 83 17 0 0
4 0 0 367116 21908 51524 0 0 68 0 118 542 88 12 0 0
5 0 0 372548 21916 51452 0 0 44 0 115 883 78 22 0 0
5 1 0 372824 22240 51596 0 0 32 644 192 426 87 13 0 0

2.6.1
procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu----
r b swpd free buff cache si so bi bo in cs us sy id wa
6 0 0 379508 26148 42532 0 0 72 0 1024 716 81 19 0 0
6 0 0 375028 26148 43076 0 0 64 0 1028 674 84 17 0 0
5 0 0 374196 26148 43144 0 0 12 0 1017 836 81 19 0 0
4 0 0 374580 26156 43068 0 0 112 0 1032 740 83 17 0 0
6 1 0 379188 26560 43140 0 0 12 776 1119 889 79 19 0 2
4 2 0 380076 27260 43392 0 0 20 1368 1178 1225 72 28 0 0
5 3 0 380844 27808 43388 0 0 44 1004 1161 1559 52 33 2 12
3 3 0 375148 28428 43584 0 0 108 1216 1224 1162 71 28 0 2
4 1 0 373036 28984 44184 0 0 36 1068 1217 774 80 19 0 1
6 1 0 380460 29528 44116 0 0 4 1024 1189 950 73 17 2 10
4 0 0 377452 29772 43940 0 0 20 1408 1141 1809 39 45 5 11
4 0 0 375596 29772 44144 0 0 56 0 1052 768 81 19 0 0
5 0 0 380588 29772 44280 0 0 0 0 1020 1088 74 26 0 0
4 0 0 376748 29780 44408 0 0 92 0 1019 1458 62 38 0 0
5 0 0 374956 29784 44676 0 0 4 0 1012 659 85 16 0 0
5 2 0 377004 30080 44584 0 0 28 584 1086 1678 57 41 0 2
3 3 0 370412 30824 44656 0 0 104 1464 1185 804 72 19 0 10
6 3 0 379884 31272 45024 0 0 16 844 1161 995 73 20 0 6
6 2 0 373420 31840 44932 0 0 8 1072 1167 1635 48 35 1 17
3 2 0 369516 32584 45140 0 0 108 1428 1159 1458 58 33 1 7
3 2 0 364268 33072 45196 0 0 48 952 1190 811 71 16 0 13
procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu----
r b swpd free buff cache si so bi bo in cs us sy id wa
5 3 0 373548 33512 45912 0 0 0 784 1129 710 86 12 0 2
6 3 0 373676 34056 45708 0 0 0 1036 1159 1444 53 32 4 12
1 4 0 368812 34728 45648 0 0 100 1280 1173 1700 44 39 3 16
4 2 0 368044 35336 45992 0 0 32 1176 1186 561 74 10 0 15
6 2 0 366508 35808 45860 0 0 12 868 1143 820 85 13 0 2
0 5 0 371628 36260 46020 0 0 0 812 1136 1732 42 33 6 20
4 1 0 363308 36836 46056 0 0 68 1116 1168 1130 44 25 1 30
4 2 0 360684 37496 46348 0 0 0 1264 1186 675 83 13 2 3
2 1 0 369068 37992 46328 0 0 0 844 1148 1499 58 31 2 9
3 2 0 365868 38588 46480 0 0 44 1188 1173 1468 58 35 0 8
5 1 0 360044 39256 46424 0 0 16 1316 1188 1020 69 26 0 5
0 1 0 367788 39860 46704 0 0 0 1112 1170 967 75 21 2 3
0 4 0 364716 40020 46748 0 0 40 2544 1226 1911 29 48 1 22
4 0 0 355180 40020 46952 0 0 0 0 1079 297 78 8 0 15
4 0 0 366636 40020 47020 0 0 0 0 1038 1381 65 35 0 0
4 1 0 362604 40028 47148 0 0 32 0 1047 1309 66 34 0 0
6 0 0 366060 40032 47484 0 0 12 0 1029 775 81 19 0 0
1 4 0 362220 40580 47276 0 0 76 1080 1146 1845 45 50 1 5
4 1 0 355116 41040 47700 0 0 128 864 1201 548 60 10 1 29
5 0 0 352492 41292 47788 0 0 16 1276 1129 507 92 8 0 0
6 0 0 363436 41296 47852 0 0 20 0 1028 1277 67 33 0 0

--
Philip Martin