"Paging" in AIX stands for any physical i/o. A page fault is simplyy when an application wants to access something in memory that is not there.

A "zero-page" fault is simply the first time a page (generally a 4k concept, but tuning can make frames (the in core page concept) be allocated in 64k, or much larger (16M byte iirc). So, for a zero-page fault, no physical i/o is needed when there is free memory available (as is your case).

Way back when, AIX was the the first UNIX to use "free memory" for file caching, rather than a set number of buffers. This has made dicusssions about paging difficult. On older UNIX (as I do not know if Solaris/HPUX/other *NIX, or Linux use file caching like AIX) the term paging referred to what AIX calls "paging space" i/o.

If I were to visit on-site to look at your situation I would look at, among other things, vmstat -I to see paging space and file paging activity.

Again, from the data above Ido not see a reason to link there is a physical i/o problem. ANd when no physical i/o is needed the paging stats can get quite high.

What would help me, is for your to rephrase your problem - or question. JUst to make sure wee are on the same page, as it were. Statistics alone can be very misleading/confusing.

---------- Post updated at 03:43 PM ---------- Previous update was at 03:34 PM ----------

Code:

                 2228 filesystem I/Os blocked with no fsbuf 
                 1537 client filesystem I/Os blocked with no fsbuf 
                 4155 external pager filesystem I/Os blocked with no fsbuf

My "feeling" regarding these statistics is that the system has some initial start up issues, because the fsbufs are too small initially - but AIX is automatically expanding them.

IIRC the AIX/Oracle document referenced above also talks about how to cause AIX to increase these buffers faster (look for the command ioo in the document).

Note: I could type all the commands here, but that is, imho, a false sense of security - as if all is covered. What I hope is that after reading you will have a new question or questions - and from your new questions I will also better understand your problem. In short, I believe in dialog, not "This is it...", or "wave a magic wand" kind of answers.