Size of /var/log/messages vs. Size of cached

[Bill]

Is there a correlation between the size of the /var/log/messages file
and the amount reported as "cached" when the top utility is run? I
see that if I put a lot of log messages in the /var/log/messages file
that the amount cached directly increases. If I then remove the /var/
log/messages file, the amount cached does not decrease.

Is this the expected behavior? In general, is there a way to keep the
amount cached down? I notice my system crashing when the amount
cached reaches a certain amount.

I am running Linux 2.6.10 on PowerPC.

[Anton Ertl]

Post by Bill
Is there a correlation between the size of the /var/log/messages file
and the amount reported as "cached" when the top utility is run? I
see that if I put a lot of log messages in the /var/log/messages file
that the amount cached directly increases.

"Cached" refers to file data that's cached in RAM, so if you write a
lot to a file, the cached file data will increase (unless there is
something else competing for RAM). So yes, writing to
/var/log/messages will tend to increase the amount cached; but
normally the amount written to /var/log/messages is small compared to
the cache size.

Post by Bill
If I then remove the /var/
log/messages file, the amount cached does not decrease.

Probably the syslogd still has the file open, so it's not really
deleted, just unlinked.

Post by Bill
Is this the expected behavior? In general, is there a way to keep the
amount cached down?

Start a memory-intensive application that does not access files.

Post by Bill
I notice my system crashing when the amount
cached reaches a certain amount.

That's a bug in your kernel. As others have mentioned, try something
more recent if possible.

- anton