Meminfo Post: 91427

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Operating Systems Linux Meminfo Post 91427 by Corona688 on Friday 2nd of December 2005 02:44:23 AM

12-02-2005

Registered User

Cache is used by the operating system to store file caches and the like, so it doesn't have to reload a frequently-used file from the hard drive over and over. But "Cache" is effectively free memory. The OS doesn't hold onto it -- if something else needs memory, cache gets thrown out and the memory used for something else. So your server is humming away at 1.5GB memory free at the moment.

That 190MB of swap, though, that is something to worry about. It only eats into swap space when it runs out of real memory; at some point in the past, it must have been at least 190 megabytes in the hole memory-wise. It could have been more -- that 190 megabytes is just the memory that's still in swap, memory in swap usually stays there until something wants it back. And when a computer is eating into it's swap space, things move very slowly.

Is there any way you could log memory and swap usage over a period of time? Something's consuming huge amounts of memory, I would guess, but you can't tell the culprit from a meminfo output.

Corona688

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LEARN ABOUT SUSE

free

FREE(1) 							Linux User's Manual							   FREE(1)

NAME

       free - Display amount of free and used memory in the system

SYNOPSIS

       free [-b | -k | -m] [-o] [-s delay ] [-t] [-V]

DESCRIPTION

       free  displays  the  total  amount of free and used physical and swap memory in the system, as well as the buffers used by the kernel.  The
       shared memory column should be ignored; it is obsolete.

   Options
       The -b switch displays the amount of memory in bytes; the -k switch (set by default) displays it in kilobytes; the -m switch displays it in
       megabytes.

       The -t switch displays a line containing the totals.

       The  -o	switch disables the display of a "buffer adjusted" line.  If the -o option is not specified, free subtracts buffer memory from the
       used memory and adds it to the free memory reported.

       The -s switch activates continuous polling delay seconds apart. You may actually specify any floating point number for delay, usleep(3)	is
       used for microsecond resolution delay times.

       The -V displays version information.

FILES

       /proc/meminfo-- memory information

SEE ALSO

       ps(1), slabtop(1), vmstat(8), top(1)

AUTHORS

       Written by Brian Edmonds.

       Send bug reports to <albert@users.sf.net>

Cohesive Systems						   20 Mar 1993								   FREE(1)