My backups have recently slowed down...
It is very peculiar and just started recently what seems to be out of
the blue. The network clients are backing up at full speed but the file
systems on the dump-host itself have slowed to about one quarter of
their normal speed. I am using dump (as opposed to tar) and what I have
observed is that a top shows kswapd and kreclaimd using 80% to 100% of
the CPU when dump is running on the dump-host.
I am running a dual 1Ghz PIII with 1G ram on the dump-host and top shows
little (or no) swap space being used (though all of memory is used, but
Linux does that no matter what). I am running redhat linux 7.2 with kernel:
2.4.7-10enterprise #1 SMP Thu Sep 6 16:48:20 EDT 2001 i686 unknown
I am running:
amanda-2.4.2p2-4.i386.rpm
dump 0.4b31 (which is the latest dump according to: http://dump.sourceforge.net)
I can't figure out what is causing kswapd and kreclaimd to go crazy when
the dump program runs, and it only happens on the dump-host. The other
5 remote systems are all running Linux 7.2 or 7.3 and dump doesn't cause
them any problems. I.e. kswapd doesn't even show up in a top on the
remote machines when dump is running.
Has anyone else ever experienced anything like this?
Any suggestions what I can try to fix it? (Please don't suggest I use
tar.) :)
Let me know if I can provide any other details of interest.
Thanks,
Dick
P.S.
A sample of the output from top exhibits the problem:
8:24pm up 1:19, 2 users, load average: 3.19, 2.88, 2.46
110 processes: 108 sleeping, 2 running, 0 zombie, 0 stopped
CPU0 states: 0.0% user, 83.0% system, 0.0% nice, 16.0% idle
CPU1 states: 1.0% user, 92.0% system, 0.0% nice, 5.0% idle
Mem: 1028364K av, 1020680K used, 7684K free, 74916K shrd, 674280K buff
Swap: 2104464K av, 1144K used, 2103320K free 140432K cached
PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME COMMAND
5 root 19 0 0 0 0 SW 99.9 0.0 16:20 kswapd
6 root 18 0 0 0 0 SW 88.4 0.0 7:45 kreclaimd
2910 amanda 9 0 1320 1284 600 D 14.8 0.1 4:07 dump
2970 rwk 13 0 1084 1080 832 R 4.1 0.1 0:00 top
1 root 9 0 520 520 452 S 0.0 0.0 0:08 init
2 root 9 0 0 0 0 SW 0.0 0.0 0:00 keventd
