[CentOS] What is eating up Swap - Thanks to all feedback

[Robert Nichols]

On 12/11/2013 07:10 AM, Götz Reinicke - IT Koordinator wrote:
> Am 10.12.13 17:18, schrieb John R Pierce:
>> On 12/10/2013 6:01 AM, Götz Reinicke - IT Koordinator wrote:
>>> recently I noticed, that one of our webservers is using swap space,
>>> while there is plenty of physical ram available.
>>>
>>> free -m
>>>                total       used       free     shared    buffers     cached
>>> Mem:          8118       2014       6103          0         85        261
>>> -/+ buffers/cache:       1667       6450
>>> Swap:         8197         77       8119
>>>
>>>
>>> It's not that much, but why?
>>
>> during idle time, dirty pages will be written to swap so they can then
>> be discarded if needed.   ignore it, it means nothing
>
> Hi thanks to all feedbacks, I'f found that the httpd is eating up swap;
> currently about 500MB while 4GB RAM are still free.

I wouldn't worry about it. It's quite normal for a long-running process like
httpd to have a few pages that are used once during startup and never
referenced again. Eventually, the kernel moves them out to swap in preference
for some extra buffer/cache space. Why you would prefer keeping long-
unreferenced pages in RAM is unclear. Of course if it is just a question of
why one server is behaving differently from the others, that is a different
matter.

-- 
Bob Nichols     "NOSPAM" is really part of my email address.
                 Do NOT delete it.