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

[Edward Ned Harvey (openindiana)]

> From: Christopher Chan [mailto:christopher.chan at bradbury.edu.hk]
> 
> 3ware did? I thought the tw driver only came out after it got bought by LSI?

Sorry, I wasn't intending to draw a distinction between 3ware and LSI.


> Until then, Areca was the only game in town but who uses hardware raid
> anymore now that we have ZFS?

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.