Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 25 Jul 2008 11:24:47 +0200
From:      "Claus Guttesen" <kometen@gmail.com>
To:        "Kris Kennaway" <kris@freebsd.org>
Cc:        FreeBSD Stable <freebsd-stable@freebsd.org>
Subject:   Re: zfs, raidz, spare and jbod
Message-ID:  <b41c75520807250224k3f1dc44alb4cb0fbd84f4c5cc@mail.gmail.com>
In-Reply-To: <48899A71.4040508@FreeBSD.org>
References:  <b41c75520807250046y4ba061a2i63d3a40b7fc76170@mail.gmail.com> <48899A71.4040508@FreeBSD.org>

next in thread | previous in thread | raw e-mail | index | archive | help
>>
>> I installed FreeBSD 7 a few days ago and upgraded to the latest stable
>> release using GENERIC kernel. I also added these entries to
>> /boot/loader.conf:
>>
>> vm.kmem_size="1536M"
>> vm.kmem_size_max="1536M"
>> vfs.zfs.prefetch_disable=1
>>
>> Initially prefetch was enabled and I would experience hangs but after
>> disabling prefetch copying large amounts of data would go along
>> without problems. To see if FreeBSD 8 (current) had better (copy)
>> performance I upgraded to current as of yesterday. After upgrading and
>> rebooting the server responded fine.
>>
>> The server is a supermicro with a quad-core harpertown e5405 with two
>> internal sata-drives and 8 GB of ram. I installed an areca arc-1680
>> sas-controller and configured it in jbod-mode. I attached an external
>> sas-cabinet with 16 sas-disks at 1 TB (931 binary GB).
>>
>> I created a raidz2 pool with 10 disks and added one spare. I copied
>> approx. 1 TB of small files (each approx. 1 MB) and during the copy I
>> simulated a disk-crash by pulling one of the disks out of the cabinet.
>> Zfs did not activate the spare and the copying stopped until I
>> rebooted after 5-10 minutes. When I performed a 'zpool status' the
>> command would not complete. I did not see any messages in
>> /var/log/message. State in top showed 'ufs-'.
>
> That means that it was UFS that hung, not ZFS.  What was the process
> backtrace, and what role does UFS play on this system?

Arghh.. Typo, I meant 'zfs-'. Pardon.

My boot-disk is plain ufs2 but the disk I pulled out was in the raidz2-pool.

-- 
regards
Claus

When lenity and cruelty play for a kingdom,
the gentlest gamester is the soonest winner.

Shakespeare



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?b41c75520807250224k3f1dc44alb4cb0fbd84f4c5cc>