High Page Faults

[daviguez]

Sorry my poor english
In 570 pseries nmon shows excessive page faults, ascents of something more than 30000 Page faults.
System: AIX 5.2 ML5
Processor Type: PowerPC_POWER5
Number Of Processors: 2
Processor Clock Speed: 1656 MHz
CPU Type: 64-bit
Kernel Type: 64-bit
Memory Size: 2816 MB

Server is running Oracle 9i and Filesystems of DB are mounted in cio mode

I have tried solve it modifying:

maxperm from 80% to 20%
minperm from 20% to 10%
maxclient from 80% to 19%
maxfree from 256 to 1152
minfree from 240 to 1080

lsps -a
Page Space Physical Volume Volume Group Size %Used Active Auto Type
hd6 hdisk0 rootvg 4608MB 1 yes yes lv

svmon -G
size inuse free pin virtual
memory 720896 703656 17240 71813 582792
pg space 1179648 3025

work pers clnt lpage
pin 71813 0 0 0
in use 582794 80589 40273 0

vmstat 2 10
System Configuration: lcpu=2 mem=2816MB
kthr memory page faults cpu
----- ----------- ------------------------ ------------ -----------
r b avm fre re pi po fr sr cy in sy cs us sy id wa
1 1 582817 17215 0 0 0 15 138 0 417 10072 734 8 5 84 3
0 0 582821 17211 0 0 0 0 0 0 371 2296 330 0 0 99 0
0 0 582821 17211 0 0 0 0 0 0 358 1174 318 0 1 99 0
0 0 583855 16177 0 0 0 0 0 0 376 1810 344 1 1 98 0
0 0 585022 15010 0 0 0 0 0 0 367 3633 347 3 1 96 0
1 0 583855 16176 0 0 0 0 0 0 367 3183 329 31 1 68 0
1 0 581895 18133 0 0 0 0 0 0 367 38934 1868 6 24 69 1
0 0 581895 18133 0 0 0 0 0 0 363 2220 319 0 0 99 0
0 0 581895 18133 0 0 0 0 0 0 372 1182 355 0 0 99 0
0 0 581895 18133 0 0 0 0 0 0 378 1247 330 0 0 99 0


Thanks a lot

 

[RodKnowlton]

Your vmstat output doesn't show any page faults, and the lsps shows that only 1% of your paging space is in use. Where did you see the > 30000 pages?

In nmon, you only need to worry about the paging activity labelled as "to Paging Space".

The number labelled as "to File System" is just a report of normal file reads and writes. In AIX, file i/o uses the paging mechanism as well.





Rod Knowlton
IBM Certified Advanced Technical Expert pSeries and AIX 5L
CompTIA Linux+
CompTIA Security+