Web Hosting Talk : Web Hosting Main Forums : Hosting Security and Technology : "Flushing" RAM

[M0NkEY]

I'm wondering if its normal for webalizer to eat a lot of ram then leave data there.

The box is at about 58% RAM usage all day after a reboot.... Then after webalizer is run once the usage goes to about 95% and stays there and there is a (Very slight) decrase in apaches response time from then on (untill the sytem is rebooted).

I'm wondering if theres a way for me to add somthing to my daily cron that will flush the ram after webalizer is run.

[Steven]

is webalizer still running when the ram usage is so high?

[M0NkEY]

Originally posted by thelinuxguy
is webalizer still running when the ram usage is so high?

No.... it finishes processing all logs...but the ram in use stays above 90% never dropping back to the pre webalizer level.

[bitserve]

OS?

Can you post the complete output of whatever you're using to check the memory use, both before and after?

[M0NkEY]

Its RH8 with the final kernal patch installed; thats how I noticed it, after rebooting the memory usage stayed like it is now:

Type           Percent    Free               Used       Size 
Physical Memory   68%     159.01 MB     338.95 MB     497.96 MB 
Disk Swap          0%     800.07 MB       0.00 KB     800.07 MB

Fluctuates from around 56-70% swap usage.
But after wabalizer runs it will turn into (and stay) at about 98% usage and use about 13-20MB of the swap even after webalizer has finished. Theres no thrashing involved... but it seems strange that the ram would stay full and the swap would remain in use even after the software is done. (then again im still fairly new to *nix machines) Maybw I'm making somthing out of nothing?

[Steven]

do a top and paste that here please

[M0NkEY]

Sorted by MEM usage.
This is before rebalizer has run becuase I reset the machine this morning.

82 processes: 79 sleeping, 2 running, 1 zombie, 0 stopped
CPU states:  0.9% user,  0.9% system,  0.0% nice, 98.0% idle
Mem:   509912K av,  354776K used,  155136K free,       0K shrd,  107448K buff
Swap:  819272K av,       0K used,  819272K free                  180144K cached

  PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
  724 mysql      9   0  7564 7564  2652 S     0.0  1.4   0:06 mysqld
  816 root       8   0  6200 6200  2628 S     0.0  1.2   0:08 miniserv.pl
  805 root       8   0  6164 6164  4100 S     1.7  1.2   0:38 httpd
  739 root       8   0  2448 2448  1824 S     0.0  0.4   0:00 sendmail
  749 smmsp      9   0  2096 2092  1608 S     0.0  0.4   0:00 sendmail
 9904 root       9   0  1492 1492  1140 S     0.0  0.2   0:00 bash
  657 root       9   0  1468 1468  1228 S     0.0  0.2   0:00 sshd
  836 Gdnscach   9   0  1552 1364   304 S     0.0  0.2   0:00 dnscache
  692 root       9   0  1168 1168  1008 S     0.0  0.2   0:00 safe_mysqld
  763 nobody     9   0  1068 1068   832 S     0.0  0.2   0:00 proftpd
  826 root       9   0  1020 1020   884 S     0.0  0.2   0:00 svscanboot
 9952 root      10   0  1012 1012   796 R     0.1  0.1   0:00 top
  673 root       9   0   880  880   732 S     0.0  0.1   0:00 xinetd
  772 root       8   0   600  600   532 S     0.0  0.1   0:00 crond
  794 daemon     9   0   560  560   504 S     0.0  0.1   0:00 atd
  515 root       9   0   556  556   480 S     0.0  0.1   0:00 syslogd
  619 root       8   0   508  508   460 S     0.0  0.0   0:00 apmd
    1 root       8   0   504  504   448 S     0.0  0.0   0:03 init
  519 root       9   0   448  448   396 S     0.0  0.0   0:00 klogd
  820 root       9   0   424  424   376 S     0.0  0.0   0:00 mingetty
  821 root       9   0   424  424   376 S     0.0  0.0   0:00 mingetty
  822 root       9   0   424  424   376 S     0.0  0.0   0:00 mingetty
  823 root       9   0   424  424   376 S     0.0  0.0   0:00 mingetty

[bitserve]

Originally posted by M0NkEY

Type           Percent    Free               Used       Size 
Physical Memory   68%     159.01 MB     338.95 MB     497.96 MB 
Disk Swap          0%     800.07 MB       0.00 KB     800.07 MB

What program is that displayed with? Maybe you should ask the author of that program how to interpret it.

I recommend pasting the output of these two commands before and after you notice these "changes":

free
ps -eo %mem,vsz,rss,command

I have a feeling that you're just not interpreting the output correctly. It is normal for Linux to use available memory up for buffering, but you're not seeing this with whatever you're using.

[M0NkEY]

Its not difficult to interpret "free" and "used" ram and swap file usage going from 0 to 13MB after webalizer is run. Its Sysinfo and basicaly displays the exact same info as "Free" but in Megabytes.

I think I found my problem though. I have webmin installed and it uses miniserv.pl. It seems that miniserv.pl goes crazy eating ram while webalizer is running.

[bitserve]

"free" displays a lot more info than your "sysinfo" command.

[MaB]

I'm not sure if you can "flush" the RAM on a Linux box - It is my belief that linux caches (buffers) frequently accessed data to the ram so that it speeds up the system - it is probably better to let linux use the ram efficiently to help speed up the system rather than to free the ram and let it sit unused