rvr split LRU minor regression ?

KOSAKI Motohiro
2008-01-16T06:18:25Z

Hi Rik

I tested new hackbench on rvr split LRU patch.

new hackbench URL is
http://people.redhat.com/mingo/cfs-scheduler/tools/hackbench.c

method of test

(1) $ ./hackbench 150 process 1000
(2) # sync; echo 3 > /proc/sys/vm/drop_caches
$ dd if=tmp10G of=/dev/null
$ ./hackbench 150 process 1000

test machine:
CPU: x86_64 1.86GHz x2
memory: 6GB

result:

2.6.24-rc6-mm1 +rvr-split-lru ratio
(small is faster)
-------------------------------------------------------------------
(1) 364.981 359.386 98.47%
(2) 364.461 387.471 106.31%

more detail:
1. /usr/bin/time command output

vanilla 2.6.24-rc6-mm1
33.74user 703.10system 6:09.56elapsed 199%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+372467minor)pagefaults 0swaps

2.6.24-rc6-mm1 + rvr-split-lru
36.22user 731.30system 6:35.16elapsed 194%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (804major+389524minor)pagefaults 0swaps

It seems increase page fault.

2.
after test (2), cat /proc/meminfo

vanilla 2.6.24-rc6-mm1

MemTotal: 5931808 kB
MemFree: 1751632 kB
Buffers: 4360 kB
Cached: 3930020 kB
SwapCached: 0 kB
Active: 46396 kB
Inactive: 3924108 kB
SwapTotal: 20972848 kB
SwapFree: 20972720 kB
Dirty: 0 kB
Writeback: 0 kB
AnonPages: 36140 kB
Mapped: 10104 kB
Slab: 160020 kB
SReclaimable: 3460 kB
SUnreclaim: 156560 kB
PageTables: 3712 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
CommitLimit: 23938752 kB
Committed_AS: 78940 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 57220 kB
VmallocChunk: 34359680999 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB

2.6.24-rc6-mm1 + rvr-split-lru

MemTotal: 5931356 kB
MemFree: 1771800 kB
Buffers: 2776 kB
Cached: 3914800 kB
SwapCached: 7940 kB
Active(anon): 21868 kB
Inactive(anon): 6560 kB
Active(file): 1722888 kB
Inactive(file): 2192128 kB
Noreclaim: 3472 kB
Mlocked: 3724 kB
SwapTotal: 20972848 kB
SwapFree: 20935032 kB
Dirty: 8 kB
Writeback: 0 kB
AnonPages: 23912 kB
Mapped: 9500 kB
Slab: 162188 kB
SReclaimable: 5544 kB
SUnreclaim: 156644 kB
PageTables: 4444 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
CommitLimit: 23938524 kB
Committed_AS: 106816 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 57220 kB
VmallocChunk: 34359680999 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB

It seems used once memory incorrect activation increased.
What do you think it?

- kosaki