-----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@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org