On 5/19/2011 9:08 PM, Andy Smith wrote: > Hi Ed, > > On Thu, May 19, 2011 at 01:26:49PM +0100, Ed W wrote: >> Ideally I would like a controller with writeback cache and BBU since >> whilst this office machine is likely quite underused, for any sensible >> amount of IO (some of the other machines we might upgrade) this seems to >> give a 10-100x increase in IOPs? For the moment it's just a nice to >> have though > > Are there actually any HBAs that have BBU without using their RAID > features? AFAIK the LSI real RAID cards allow this. To get them into a JBOD mode you have to create a single drive RAID 0 of each disk and export it. By doing so the RAID firmware is actually active, though not really doing anything, so you get the cache and BBU benefit of the controller. One of the XFS developers, Dave Chinner, posted this to the XFS list quite some time ago when we discussed hardware vs software RAID setups. -- Stan -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
