上了aix O_CIO 後 %Comp提升至99.3

显示全部楼层 · 2010-3-1 11:19:07

看來file system buffer cache 的確降低了!!
---------------------------------------------------------------------------------------------------
Mon Apr 25 09:01:13 2011 Interval:2 Cswitch 893Readch1148.5K

Syscall4565Writech111.1K
Kernel2.7 |#
|Reads 226Rawin 0
User1.1 |#
|Writes120Ttyout393
Wait 11.8 |####
|Forks 0Igets 0
Idle 84.5 |########################|Execs 0Namei68

Runqueue0.0Dirblk0
NetworkKBPS I-PackO-Pack KB-InKB-OutWaitqueue 0.0
en0 132.1100.079.522.7 109.4
lo0 0.00.0 0.0 0.0 0.0PAGING MEMORY

Faults446Real,MB7744
DiskBusy% KBPS TPS KB-Read KB-WritSteals0% Comp 99.3
hdisk3 44.5 1082.8 137.51080.0 2.8PgspIn0% Noncomp 0.6
hdisk20.55.5 3.5 2.8 2.8PgspOut 0% Client1.6
hdisk10.52.0 0.5 2.0 0.0PageIn0
hdisk00.00.0 0.0 0.0 0.0PageOut 0PAGING SPACE
dac10.05.5 3.5 2.8 2.8Sios
0Size,MB 16384
cd0 0.00.0 0.0 0.0 0.0
% Used8.8
dac1-utm0.00.0 0.0 0.0 0.0NFS (calls/sec)% Free 91.1
dac00.0 1082.8 137.51080.0 2.8ServerV2 0
dac0-utm0.00.0 0.0 0.0 0.0ClientV2 0 Press:

ServerV3 0 "h" for help
Name
PIDCPU%PgSp Owner ClientV3 0 "q" to quit

千问 · 2010-3-1 11:19:07

太高未必是好事情把

千问 · 2010-3-1 11:19:07

都改CIO了？

千问 · 2010-3-1 11:19:07

昨天才改CIO
現在還在觀察中現在系統正常
只要 paging space 不異常增加
我想應該就沒事

千问 · 2010-3-1 11:19:07

是改文件系统的属性，还是设置FILESYSTEMIO_OPTIONS来使用CIO的？

千问 · 2010-3-1 11:19:07

修改AIX操作系统FS的属性可以启用CIO，修改FILESYSTEMIO_OPTIONS可以使用操作系统的DIO特性。CIO和DIO还是有区别的

千问 · 2010-3-1 11:19:07

透過 FILESYSTEMIO_OPTIONS 使用CIO
用truss 確認過 open file 時會啟用O_CIO
不建議用mount 方式使用cio

千问 · 2010-3-1 11:19:07

SQL>alter database open;
------------------------------------------------
DBW process監控視窗:
open("/u2/oradb/oradata/toptest/system01.dbf", O_RDONLY|O_CIO|O_LARGEFILE) = 18
open("/etc/vfs", O_RDONLY)
= 19
open("/u2/oradb/oradata/toptest/system01.dbf", O_RDONLY|O_LARGEFILE) = 18
open("/u2/oradb/oradata/toptest/system01.dbf", O_RDWR|O_CIO|O_DSYNC|O_LARGEFILE) = 18
open("/u2/oradb/oradata/toptest/undotbs01.dbf", O_RDONLY|O_CIO|O_LARGEFILE) = 19
open("/etc/vfs", O_RDONLY)
= 20
open("/u2/oradb/oradata/toptest/undotbs01.dbf", O_RDONLY|O_LARGEFILE) = 19
open("/u2/oradb/oradata/toptest/undotbs01.dbf", O_RDWR|O_CIO|O_DSYNC|O_LARGEFILE) = 19
open("/u2/oradb/oradata/toptest/sysaux01.dbf", O_RDONLY|O_CIO|O_LARGEFILE) = 20

千问 · 2010-3-1 11:19:07

原帖由 aks5201314 于 2011-4-25 11:47 发表
修改AIX操作系统FS的属性可以启用CIO，修改FILESYSTEMIO_OPTIONS可以使用操作系统的DIO特性。CIO和DIO还是有区别的
非，改该参数即可用CIO，DIO．

千问 · 2010-3-1 11:19:07

CIO不是光为了降低非计算内存的，而且计算内存你用了99.3%绝对不是好事，很容易paging