Re: ext4 is faster with LVM than without, and other filesystem benchmarks

[Bernd Eckenfels]

In article <20100507142310.GF13143@xxxxxxxxxx> you wrote:
> I think the most surprising result of the benchmarks is that ext4
> seems to be significantly faster under LVM than on the raw /dev/sdd1
> partition. Without LVM the variance in run times is much larger.

Sounds like the syncs/barriers never reach the disk with LVM. What mount
journal/sync options did you use?  default?  Is dmesg telling you that
barriers have been turned off for the lvm case?  IF yo uwant it fast and
dirty try nobarrier,data=writeback :)

Greetings
Bernd
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