[OmniOS-discuss] zfs compression limits write throughput to 100MB/sec

[Saso Kiselkov]

On 9/14/15 9:05 PM, Doug Hughes wrote:
> Probably something for Illumos, but you guys may have seen this or may
> like to know.
> 
> I've got a 10g connected Xyratex box running OmniOS, and I noticed that
> no matter how many streams (1, 2, 3) I only get 100MB/sec write
> throughput and it just tops out. Even with 1 stream. This is with the
> default lzjb compression on (fast option).
> 
> I turned off compression and have 2 streams running now and am getting
> about 250-600MB/sec in aggregate. Much better!
> 
> The compress ratio was only 1.02x - 1.03x so it's no great loss on this
> data. I just thought the 100MB/sec speed limit was interesting.

Try setting compression=lz4. It should perform much, much better than
lzjb on incompressible data.

-- 
Saso