Feizhou spake the following on 6/6/2006 7:37 PM:
William L. Maltby wrote:
On Tue, 2006-06-06 at 13:45 +0800, Feizhou wrote:
Sam Drinkard wrote:
William L. Maltby wrote:
I need to look more into it, but before I start the long and arduous "googling my life away" process, I figured someone might know the answer. I've read the man pages several times and they didn't change! :-(
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most of the 'swapped' data is probably sitting in the cache or buffers?
Here is an example:
https://bugzilla.redhat.com/bugzilla/attachment.cgi?id=129064
Thanks to the patience and efforts of all, Rodrigo, Les, Sam, Feizhou ... I think I've got a handle on this thing.
The only mistake was turning on "SWAP" in top.
I can see difficulty in programming to get a *meaningful* swap figure: that is, one that represents either real swapped memory, or its current needs or its potential maximum need. That assumes one can make the decision as to which to show.
Others already show (apparently) current swap (free, top's summary lines), so what could one put under the "SWAP" column? I now think that it was the maximum possible swap needed for each process, as you all suggested.
:)
Text shared from program segments and libraries, shared data, buffers, cache, parts already swapped, parts marked for swap but not committed yet,... What would show under the "swap top"? From a programming POV, showing anything but the virtual memory use could be complex and have a tight coupling to the VM implementation details, increasing maintenance for a little used data column too.
I am comfortable that "SWAP" only shows the simplest to obtain value and the only problem is that a better explanation is could be provided in the man pages for top.
Eh? I thought that problem kind of exists for all man pages!
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And we do know that a fix for the lock up in Sam's and my machine is apparently in the pipeline for U4.
If I was a paying customer....
When upstream opens the floodgates of patches, CentOS will have them within a week, usually less, depending on if they break something.