Poor 3ware Performance Fix (in some cases)
While I’m on the topic of 3ware cards and performance issues (or lack of performance thereof) I thought I’d share this as well:
[SCSI] 3w-9xxx: fix abysmal write performance on some motherboards
The fix is as simple as grabbing the driver source from 3ware and inserting a call to pci_try_set_mwi() right after pci_set_master() as some motherboards won’t do this be default.
Also, there’s a RHEL bug on the same thing that refers to the same fix. This Ubuntu bug also refers to performance issues with a 3ware card. I started looking in to this a bit after reading this thread at Storage Review.
Disclaimer: when I wrote this, I haven’t tried it yet. Your mileage may vary.