On 28/01/2009 23:56, Greg Freemyer wrote:
Once discard calls get into linux file systems mdraid and/or device mapper could implement linux's own thin provisioning implementation. Even with traditional disks that don't support unmap. I gather that is what the EMCs of the world will be doing in their platforms. http://en.wikipedia.org/wiki/Thin_provisioning
Sounds more like a device mapper or LVM thing (than md/RAID) to me, but I'd definitely agree that this would be another great reason for block devices to implement map/unmap.
And I wonder if there's room for another dm/md device type which just implements these usage maps over traditional devices which don't support unmap (much as I was wondering a few weeks back about a soft DIF implementation over e.g. SATA devices). Darn it, I might just have to dig out my school books on C; it's a while since I offered a kernel patch.
Cheers, John. -- 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
