[Asterisk-Users] 1.0_stable is or isn't? (Was: No ringing tone...)

[Steven Critchfield]

On Sat, 2004-04-10 at 11:51, Bob Klepfer wrote:

> (I *have* noticed RAM almost completely filled, but no swap used...a 
> reboot freed a bunch and I think that fixed some issues.  We're a small 
> company and restarting * or rebooting the server isn't that big a deal.)

Once again we must teach a newbie about memory usage and the tools they
use to check it. If you where looking at memory usage via top, you nee
to subtract from the used memory the buffers and cache. Buffers and
cache can be freed anytime the system needs memory. It rarely will
reduce unless you need that physical memory. 

Linux, like any other modern OS, will use all the physical memory
possible to cache the harddrive. Remember your hardrive access time is
measured in milliseconds, and usually in the 5-9 millisecond range. Your
memory is going to be measured in nanosecond or less. So realize that
Linux is going to try and use as much memory as possible for any file
access it thinks you will do often enough to get some speed increases.
Think of how many audio files you touched, the config files, any
libraries your tools link with, any binaries you have run, and any log
files you have looked at. 

The cool thing is Linux can just discard the cached entries when a
application needs real RAM. Don't worry about your RAM usage until you
see swap climbing and/or the buffers and cache dropping down to near
zero. 
-- 
Steven Critchfield <critch at basesys.com>