On 05/26/2010 04:50 PM, Anthony Liguori wrote:
In fact, btrfs is currently unusable for virt because O_SYNC writes
inflate a guest write to a host write. by a huge factor (50x-100x).
cache=writethrough is 100% unusable, cache=writeback is barely
tolerable. As of 2.6.32, cache=volatile is probably required to get
something resembling reasonable performance on btrfs.
Of course, we expect that btrfs will improve in time, but still it
doesn't seem to be fsync friendly.
So you're suggesting that anyone who uses virt on btrfs should be
prepared to deal with data corruption on host failure?
No.
That sounds to me like btrfs isn't ready for real workloads.
The btrfs developers aren't saying anything different. But people still
want to try it out (to wire up snapshotting to management, for example).
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error compiling committee.c: too many arguments to function
