[OpenIndiana-discuss] AMCC/3Ware 9550SX-8LP

[Sašo Kiselkov]

On 01/24/2013 02:39 PM, Edward Ned Harvey (openindiana) wrote:
> 
> Based on my extensive work benchmarking zfs systems, I can say this:  The default write performance on a plain old sas/sata card (without SSD) is horrible by comparison to the following alternatives:
> 
> You get a huge increase if you add the HBA write buffer.  
> You get better still (by just a little) if you disable the HBA write buffer (go back to the plain old SATA card) and add a SSD log device instead.
> You get the best performance (of course) if you eliminate both the HBA write buffer and SSD log device, while also disabling ZIL.  But this configuration is only "safe" for certain types of usage.

Just a quick question and I think I know the answer: you mean *sync*
write performance, right? Otherwise none of those above matter and the
HBA should act as just a fat pipe from RAM to disks.

Cheers,
--
Saso