On Wed, Nov 22, 2006 at 06:12:06PM +0000, Dieter wrote: > > > > > time ls on a small directory on disk2 > > > > >=3D20 > > > > > real 4m51.911s > > > > > user 0m0.000s > > > > > sys 0m0.002s > > > > >=3D20 > > > > > I expect access to a busy disk to take longer, but 5 minutes is > > > > > a bit much. And that's the root directory of the filesystem, > > > > > it didn't have to follow a long chain of directories to get there. > > > > >=3D20 > > > > > Sometimes I see long delays when accessing disk3, but it is > > > > > behaving at the moment. > > > >=20 > > > > ls still has to acquire a number of locks in order to be sure that the > > > > contents of the directory aren't changing. If there are lots of other > > > > processes all competing for these locks, it will be slow. It looks > > > > like that's the case on your system, although details of your workload > > > > have been trimmed from your email. > > >=20 > > > In telnet window 1: > > >=20 > > > cd /disk1/ > > > cp -ip very_big_file /disk2/bar/ (the workload) > > >=20 > > > In telnet window 2: > > >=20 > > > time ls /disk3/foo1/ (make sure time and ls are cached in memory) > > > time ls /disk3/foo2/ (see timing numbers above) > > > time ls /disk2/ (see timing numbers above) > > >=20 > > > The /disk2/ directory is small, only contains 3 directories and .snap > > >=20 > > > Would the cp into /disk2/bar/ lock the /disk2/ directory? > > > > It shouldn't do. > > > > What scheduler are you using? > > kern.sched.name: 4BSD > kern.sched.quantum: 100000 > kern.sched.preemption: 1
OK, that's correct. Can you also provide details of your disk hardware (e.g. dmesg) and kernel configuration? Kris
pgpyxbAHgYhIR.pgp
Description: PGP signature
