Mailinglist Archive: opensuse (1986 mails)

< Previous Next >
Re: [opensuse] wait times excessive high {Suse 10.3 & 11}
  • From: "Carlos E. R." <robin.listas@xxxxxxxxxxxxxx>
  • Date: Wed, 19 Nov 2008 13:16:39 +0100 (CET)
  • Message-id: <alpine.LSU.2.00.0811191311180.6163@xxxxxxxxxxxxxxxx>
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1



On Tuesday, 2008-11-18 at 16:42 -0800, James D. Parra wrote:

Trying to find why almost every process that requires IO has near 100% wait
times.

Even a simple 'cp' command has enormous wait times and doesn't appear at or
near the top of the list when running 'top'. This was occurring when
writing to a raid, but have tested writing to the system drive and the same
thing occurs.

Running the 'cp command copying a 19GB file from /tmp/file1 /tmp/file2 will
take 50 minutes

Not normal.

Mem: 33020488k total, 5782932k used, 27237556k free, 316k buffers
Swap: 8393952k total, 0k used, 8393952k free, 5562388k cached

No used swap, lots of cached memory, lots of free memory...

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1 root 20 0 864 336 272 S 0 0.0 0:01.28 init
2 root 15 -5 0 0 0 S 0 0.0 0:00.00 kthreadd
3 root RT -5 0 0 0 S 0 0.0 0:00.00 migration/0
4 root 15 -5 0 0 0 S 0 0.0 0:00.00 ksoftirqd/0
5 root RT -5 0 0 0 S 0 0.0 0:00.00 migration/1
6 root 15 -5 0 0 0 S 0 0.0 0:00.00 ksoftirqd/1
7 root RT -5 0 0 0 S 0 0.0 0:00.00 migration/2
8 root 15 -5 0 0 0 S 0 0.0 0:00.00 ksoftirqd/2
9 root RT -5 0 0 0 S 0 0.0 0:00.00 migration/3
10 root 15 -5 0 0 0 S 0 0.0 0:00.00 ksoftirqd/3
11 root RT -5 0 0 0 S 0 0.0 0:00.00 migration/4
12 root 15 -5 0 0 0 S 0 0.0 0:00.00 ksoftirqd/4
13 root RT -5 0 0 0 S 0 0.0 0:00.00 migration/5
14 root 15 -5 0 0 0 S 0 0.0 0:00.00 ksoftirqd/5
15 root RT -5 0 0 0 S 0 0.0 0:00.00 migration/6
<snip>

What is that "migration" task? Raid migration, perhaps? I'm wild guessing, but if that is a task copying from one mirror to another or such, it would explain the problem. That "migration" runs at Real Time priority, I think.


'cp' is not showing up, but it is running;

root 3915 0.2 0.0 8296 696 pts/0 D+ 15:20 0:02 cp file1
file2

There is an option in "top" to show at what function it is waiting.

- -- Cheers,
Carlos E. R.

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.9 (GNU/Linux)

iEUEARECAAYFAkkkA6kACgkQtTMYHG2NR9XKXgCYiuR5BcY927M4vad9j1wdY3Oi
qQCfVsOdD4nhaU6Dsn0RjZGgR6fzob4=
=4UVA
-----END PGP SIGNATURE-----
--
To unsubscribe, e-mail: opensuse+unsubscribe@xxxxxxxxxxxx
For additional commands, e-mail: opensuse+help@xxxxxxxxxxxx

< Previous Next >
References