Roch wrote:
Michael Schuster writes:
> IHAC who is using a very similar test (cp -pr /zpool1/Studio11
> /zpool1/Studio11.copy) and is seeing behaviour similar to what we've
> seen described here; BUT since he's using a single-CPU box (SunBlade
> 1500) and has a single disk in his pool, every time the CPU goes into
> "100%-mode", interactive usability is reduced to zero for 1-2
> seconds. This is of course undesirable.
>
> + Do we have any bug IDs or RFEs addressing this?
> + Is there any tuning the customer can try (he's willing to do anything with the machine, apart from donating it to me :-)? (we've already tried "echo txg_time/W1 | mdb -kw", with no improvement - on the contrary, machine returned to "usable" state hardly at all).
> + has customer (and I) missed a constraint about when/where to deploy zfs?
>
> thx
> Michael
>
>
> This message posted from opensolaris.org
> _______________________________________________
> zfs-discuss mailing list
> zfs-discuss@opensolaris.org
> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
What is the desired behavior ?
a system that doesn't freeze every few seconds just because someone is busy
on a zpool.
The workload (cp with compression) overloads the single
CPU. Response time is bound to be affected.
I wasn't aware that compression was involved here. Does raidz imply
compression? I thought not.
also note: my customer is NOT using compression.
I am not sure how we could get compression to run at a low
priority level, holding up write syscalls.
I suggest to Buy a second CPU or turn off compression.
see above - compression is off (I checked :-)
Michael
--
Michael Schuster +49 89 46008-2974 / x62974
visit the online support center: http://www.sun.com/osc/
Recursion, n.: see 'Recursion'
_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
