Originally posted by: SystemAdmin

My test p550 with AIX 5.3L functions well with its paging , no busy sign as I noticed this parameter under the sys0 having value 33, minpout=24; while my prod p550 AIX 5.3 has significant paging busy problem and the maxpout=0 as well as minpout=0. While both machine´s j2_nPagesPerWriteBehindCluster (of ioo) is 32. According to AIX lib, the maxpout should be higher or equal it at least. Should this the cause?

Originally posted by: vbaranov

"maxpout/minpout" watermarks are so-called "Disk-I/O pacing", which is intended to prevent programs that generate very large amounts of output from saturating the system's I/O facilities and causing the response times of less-demanding programs to deteriorate. Neither IBM doc does mention it affects paging, nor I think it is a case in your case.
If "paging space I/Os blocked with no psbuf" increased rapidly over the time in "vmstat -v" output, you should increase "numfsbufs" using "ioo". Read the detailed explanation at http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.prftungd/doc/prftungd/disk_io_pacing.htm
(remove space(s) in the link above if any appears in the message' body).
This document contains almost everything you may need regarding the performance tuning.

Originally posted by: SystemAdmin

I had increase the numfsbufs to 1024 from 96 (default). How high I should go to? The is a production box. even we are not 24x7, My boss does not like keeping reboot the server.
By an application from Oracle - OSWatcher, I can clearly see the avm is constantly increasing during the day, ie some memory leaks are happening.