On Thu, Nov 18, 2010 at 05:16:36PM -0800, Greg Freemyer wrote: > I agree with Mark. When you say "make coalescing work" it sounds like > major overkill. > > FITRIM should be able to lock a group of non-contiguous free ranges, > send them down to the block layer as a single pre-coalesced set, and > the block layer just needs to pass it on in a synchronous way. Then > when that group of ranges is discarded, FITRIM releases the locks. Given that you know the Linux I/O stack and hardware so well may I volunteer you to implement it? Including remapping the multiple ranges in device mapper, and dealing with the incompatible range formats for TRIM vs UNMAP. If your implementation is clean enough I'm pretty sure no one will object to merge it. > Every TRIM causes a cache flush anyway on the SSD, so the synchronous > aspect of the process should not be a problem. (Maybe SCSI with thin > provisioning would see a performance hit?) What's your evidence? -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
