swapper

[yulianto piyut]

hi all,

I have a system with top of processes is swapper.

CPU TTY PID USERNAME PRI NI SIZE RES STATE TIME %WCPU %CPU COMMAND
4 ? 0 root 127 20 32K 0K sleep 106:33 13.82 13.79 swapper
0 pts/0 9354 yulianto 178 20 14156K 12188K run 0:00 2.72 1.50 top
3 ? 9174 root 154 20 5988K 768K sleep 0:00 2.15 1.44 sshd:
5 ? 2339 oracle 152 0 86912K 11016K run 11:32 1.17 1.17 ocssd.bin

what happened ?

[A. Clay Stephenson]

Swapper's job is to deactivate processes when the system is under memory pressure. I suspect that if you run vmstat, you are going to see a high pageout rate which means that your box is under high memory pressure.

[yulianto piyut]

clay,

output form vmstat and swapinfo -tam

$ vmstat 4
procs memory page faults cpu
r b w avm free re at pi po fr de sr in sy cs us sy id
1 1 0 507608 23050 650 89 81 134 0 0 573 3701 40738 1967 4 3 92
1 1 0 507608 22813 416 87 0 0 0 0 0 2256 16731 711 0 3 96
1 1 0 494074 22994 409 83 0 0 0 0 0 2410 21558 861 1 3 96
1 1 0 494074 22886 423 87 0 0 0 0 0 2307 18996 773 1 3 96
1 2 0 482938 23058 420 81 7 0 0 0 0 2386 19654 862 0 4 96
1 2 0 482938 23058 351 70 3 0 0 0 0 2303 16586 751 1 3 96
1 2 0 482938 23058 417 85 2 0 0 0 0 2266 17326 728 0 3 97
$ /usr/sbin/swapinfo -tam
Mb Mb Mb PCT START/ Mb
TYPE AVAIL USED FREE USED LIMIT RESERVE PRI NAME
dev 32768 6409 26359 20% 0 - 1 /dev/vg00/lvol2
reserve - 20847 -20847
memory 12606 4951 7655 39%
total 45374 32207 13167 71% - 0 -

pageout is 0.

[skt_skt]

which is the OS version?Paste the output of "sar -w 3 3" & "sar -c 3 3"

[yulianto piyut]

hi santosh,

nice to talk with u ;)

$ uname -a
HP-UX eaipdb3 B.11.11 U 9000/800 50865584 unlimited-user license
$ sar -w 3 3

HP-UX eaipdb3 B.11.11 U 9000/800 08/07/07

10:59:00 swpin/s bswin/s swpot/s bswot/s pswch/s
10:59:03 0.00 0.0 0.00 0.0 681
10:59:06 3.32 0.0 3.32 0.0 711
10:59:09 0.00 0.0 0.00 0.0 685

Average 1.11 0.0 1.11 0.0 692
$ sar -c 3 3

HP-UX eaipdb3 B.11.11 U 9000/800 08/07/07

10:59:13 scall/s sread/s swrit/s fork/s exec/s rchar/s wchar/s
10:59:16 48741 2544 69 24.92 25.25 13793042 4082
10:59:19 50446 601 69 27.91 27.91 12938461 5443
10:59:22 17595 456 61 18.67 18.67 5921451 4096

Average 38951 1201 66 23.84 23.95 10889689 4541
$

[skt_skt]

"sar -w 3 3" shows the system is doing enough swapping.

how much is the Physical MEM and swap space?I would say to identify the swap usage statics through tools like PV; the heavy swap utlization means swapper is doing a very good job and CPU is the engine oil to run the show.

[whiteknight]

Batul,

If the swapper constantly high, you need to aware, because memory pressure is high,also the output you show high page in/out, potential performance issue.

I would recommend monitor constantly from Glance or engaged HP for Performance assessment Services.

[yulianto piyut]

hi santosh,

the physical mem is 16 GB. server runing oracle RAC.

-yut-