Subject: Re: Excessive swapping / Memory problems
To: Chuck Swiger <cswiger@mac.com>
From: Vincent van Scherpenseel <mailinglists@vanscherpenseel.nl>
List: netbsd-users
Date: 09/06/2006 22:55:31
Chuck Swiger wrote:
> On Sep 6, 2006, at 12:40 PM, Vincent van Scherpenseel wrote:
>>> "top -o size" will show you which processes are requiring lots of 
>>> memory; it's possible that one of them is leaking, or it may simply 
>>> be that you are trying to run too much on a machine with limited 
>>> RAM.  Increasing the amount of RAM in your machine is probably going 
>>> to improve the performance of the system significantly...
>>
>> The strange thing is that it's a very low loaded machine, only running 
>> an SMTP server for my daily mail (about 50 messages a day) and a 
>> webserver for my personal website (http://vincent.vanscherpenseel.nl). 
>> Most of the visitors are spambots targeting the blog comment system (I 
>> really need to implement a CAPTCHA check, I know).
>>
>> Here is the top output of top -o size:
>>
>>   PID USERNAME PRI NICE   SIZE   RES STATE      TIME   WCPU    CPU 
>> COMMAND
>>  9747 www       -4    0    35M    4K semwait    0:32  0.00%  0.00% httpd
> [ ... ]
> 
> Ah, eight to ten 35MB apache children will consume most or all of your 
> RAM and swap space.
> 
> Apache normally uses a lot less; a stock Apache-1 without anything 
> expensive will take 5-8MB, and even Apache-2 + mod_perl or PHP takes 
> around 15 - 20MB; perhaps you can reduce the max # of children running 
> or remove a module or two that is bumping your memory usage up so much...

Yes, but how does it come that it's taking 35megabytes? I'm running 
Apache2 with PHP. I never had these problems. Like I said: I hardly ever 
get any visitors so I could probably reduce the number of childs. 
However, I find it rather strange that these problems suddenly occur.

Kind regards,
Vincent van Scherpenseel