Originally posted by: SystemAdmin

This status bother me for while and do not know how to tackle it. Here is a snapshot of my AIX 5.3L p550 (4g memory ,2 CPU)
Topas Monitor for host: baanserver EVENTS/QUEUES FILE/TTY
Fri May 25 07:58:51 2007 Interval: 2 Cswitch 412 Readch 178.3K
Syscall 2090 Writech 47877
Kernel 0.9 |# | Reads 161 Rawin 0
User 2.4 |# | Writes 149 Ttyout 426
Wait 0.3 |# | Forks 0 Igets 0
Idle 96.4 |############################| Execs 0 Namei 42
Runqueue 0.0 Dirblk 0
Network KBPS I-Pack O-Pack KB-In KB-Out Waitqueue 0.0
en0 8.5 9.0 11.5 0.4 8.1
lo0 0.9 3.0 3.0 0.5 0.5 PAGING MEMORY
Faults 0 Real,MB 3792
Disk Busy% KBPS TPS KB-Read KB-Writ Steals 0 % Comp 55.6
hdisk0 1.5 2.0 0.5 0.0 2.0 PgspIn 0 % Noncomp 44.7
hdisk2 0.0 0.0 0.0 0.0 0.0 PgspOut 0 % Client 46.0
hdisk3 0.0 0.0 0.0 0.0 0.0 PageIn 0
hdisk1 0.0 0.0 0.0 0.0 0.0 PageOut 0 PAGING SPACE
cd0 0.0 0.0 0.0 0.0 0.0 Sios 0 Size,MB 6272
% Used 44.3
Name PID CPU% PgSp Owner NFS (calls/sec) % Free 55.6

1. lsps -a

Page Space Physical Volume Volume Group Size %Used Active Auto Type
hd6 hdisk0 rootvg 6272MB 44 yes yes lv

1. svmon -G

size inuse free pin virtual
memory 970752 963774 6978 247720 1061833
pg space 1605632 703340

work pers clnt
pin 247720 0 0
in use 526068 0 437706

I noticed that the %use nad clnt (%client) value are high especially in the morning before majority of employees began to use the system (a BAAN and Oracle 10gR2). These values will gradually drop during the business hours, 10 AM ~ 4 PM, when more user are on. Do I misunderstand the meanings of %use and %client or they did indicate something needed to tune? How do I start?

Originally posted by: nh4aix

Hello...

%use in paging space... this means that 44% of your paging space has been allocated to processes... this is not bad or good... when a process starts, it gets some quanity of page space pages... What would be MUCH more troublesome is if you were paging, which you are not, because PageIn and PageOut are zero...

%client... at a high level, AIX divides memory into two buckets: working memory for programs, swap spaces, kernel, SGA's, shared memory, etc. (This is called "Comp" on topas) and a 2nd bucket for file cache. This 2nd cache is subdivided into "client" & "non-comp"... JFS2 filesystems and NFS filesystems are "client". The intent is to cache filesystems in memory to prevent I/O's... %client will tell you how much of your memory you are using for this file cache.. Again, 46% is not good or bad. Nor is it good or bad that it grows or drops... The fact that no paging is being done (see above), says that AIX is effectively managing the memory....

I have simplied things a little bit... there are tunables that can affect the behaviour, but at this point, I see no reason to make any changes...

next steps for your are to understand AIX's Virtual Memory Manager I would suggest starting with that topic in the Information Center: http://publib.boulder.ibm.com/infocenter/pseries/v5r3/topic/com.ibm.aix.baseadmn/doc/baseadmndita/virt_mem_mgr.htm?resultof=%22%76%69%72%74%75%61%6c%22%20%22%6d%65%6d%6f%72%79%22%20%22%6d%65%6d%6f%72%69%22%20%22%6d%61%6e%61%67%65%72%22%20%22%6d%61%6e%61%67%22%20

Just my two cents...
Joe