AIX Swap file size.

[butchrecon]

I have a proble. I have a AIX 4.3.3.8 Server with 256M RAM With 2 9 gig Hard Drives and a RAID 5 array with 36Gig. The system is not running much but the OS and a database progam. The issue is the SWAP FILE IS HUGE. 600 meg. and it is constantly accessing it. I cant figure out why? I am no AIX guru so I need help. Any one have any Ideas? James Collins
Field Service Engineer
A+, MCP

email: butchrecon@skyenet.net

Please let us (Tek-tips members) know if the solutions we provide are helpful to you. Not only do they help you but they may help others.

 

[bjverzal]

How can you tell the system is accessing it ?

 

[butchrecon]

I used a program called monitor. It tells me how much RAM I have, how much used and how much free. It also tells me page space, free and used. On both RAM and page both are nearly maxed. I know I must have a runaway process or leaky application somewhere I just dont know how to find them. James Collins
Field Service Engineer
A+, MCP

email: butchrecon@skyenet.net

Please let us (Tek-tips members) know if the solutions we provide are helpful to you. Not only do they help you but they may help others.

 

[bjverzal]

With UNIX, all memory is allocated to the OS, and is doled out from there as requested. The paging space issue may be a real issue...

Send me the output of a "vmstat 3 10" command.

Bill.

 

[butchrecon]

This is the rintout of vmstat.

kthr memory page faults cpu
r b avm fre re pi po fr sr cy in sy cs us sy id wa
0 1 20083 463 0 1 1 49 126 0 229 972 161 21 7 68 3
0 1 20083 434 0 0 0 0 0 0 244 910 179 2 2 93 3
0 1 20406 120 0 0 0 12 55 0 213 1474 127 4 8 88 0
0 1 20410 125 0 0 0 3 27 0 348 1008 339 4 3 93 0
0 1 20410 138 0 0 0 9 39 0 266 348 147 1 2 91 6
0 1 20733 121 0 0 3 111 377 0 226 1273 78 4 2 93 0
0 1 20733 121 0 0 0 0 0 0 173 58 48 0 0 99 0
0 1 20733 121 0 0 0 0 0 0 174 66 55 0 0 99 0
0 1 20733 121 0 0 0 0 0 0 172 65 50 0 0 99 0
0 1 21008 157 0 0 50 113 292 0 254 634 104 1 8 80 11 James Collins
Field Service Engineer
A+, MCP

email: butchrecon@skyenet.net

Please let us (Tek-tips members) know if the solutions we provide are helpful to you. Not only do they help you but they may help others.

 

[bjverzal]

Columns 6 and 7 describe a system that is paging. If > 0, then there were some pages in (column 6) or pages out (column 7). From the output you sent, I don't see anything for concern.

The last 4 columns show CPU utilization. User, System, Idle and Waiting I/O. If User + System > 70 on an extended basis, you have a CPU/memory problem. If I/O > 10-20 on an extended time, you have a bottleneck (and/or a very I/O intensive application running).

There was a slight amount of paging on samples 1, 6 and 10, but nothing for concern.

If the first column > # CPU's, you have a CPU bottleneck.

Does this Help ?

Bill.

 

[butchrecon]

A CPU bottleneck? Any ideas what would cause that? I dont know a whole lot about AIX. But I am learning. James Collins
Field Service Engineer
A+, MCP

email: butchrecon@skyenet.net

Please let us (Tek-tips members) know if the solutions we provide are helpful to you. Not only do they help you but they may help others.

 

[bjverzal]

You don't have one. Your first column is all zero. That indicates there was nothing waiting for CPU resources. I guess I was jumping around too much (sorry) LOL

Bill.

 

[butchrecon]

Well the issue is that there is a 600 meg swap file that is CONSTANTLY in use. Is that normal? James Collins
Field Service Engineer
A+, MCP

email: butchrecon@skyenet.net

Please let us (Tek-tips members) know if the solutions we provide are helpful to you. Not only do they help you but they may help others.

 

[bjverzal]

How can you tell it is in use ?

Bill.

 

[bjverzal]

Send me an "lsps -s" and a "lsps -a".

Bill.

 

[butchrecon]

Use a program called monitor. It has RAM useage is full and so is swap. James Collins
Field Service Engineer
A+, MCP

email: butchrecon@skyenet.net

Please let us (Tek-tips members) know if the solutions we provide are helpful to you. Not only do they help you but they may help others.

 

[axelsche]

As long as you dont have a lot of paging (less than 20 % of RAM is ok). You dont have a problem with your Swap Space.
(Thats what Oracle support told me some time ago)

Axel

 

[gileb]

Hi,

Could you send output from /usr/samples/kernel/vmtune ?

thx

 

[butchrecon]

Thanks to all those who were helping. The problem turned out to be that when I was not looking someone added a second swap file to the system and it did not like that. James Collins
Field Service Engineer
A+, MCP

email: butchrecon@skyenet.net

Please let us (Tek-tips members) know if the solutions we provide are helpful to you. Not only do they help you but they may help others.