thanks neil, i will try to read and make some patch, my focus is ssd optimization, at hardware level (hw raid) i didn't see any good improvement good = a good read balance (based on queue and disk read rate), trim support ---- good read balance = round robin or another time based algorithm (can be cpu intensive), i didn't found yet how to get queue of linux bio (mirrors) trim support - nothing to report, it's a 'feature request' for long term (after badblock and others features) ----- ps... neil what are you thinking about badblock and layout? for example... reading from a bad block will be internaly (md source code) remapped to a good block? or just try read/write to another device? in other words we will have 'dynamic' layout? 2011/2/22 NeilBrown <neilb@xxxxxxx>: > On Mon, 21 Feb 2011 23:27:26 -0300 Roberto Spadim <roberto@xxxxxxxxxxxxx> > wrote: > >> tape drive = harddisk with only one head, the head can't move, only >> the tape (disk/plate or any other name you want) >> >> could we get back and answer the main question? >> -------------------------- >> getting back to the first question, can MD support trim? yes/no/not >> now/some levels and layouts only? >> > > MD currently doesn't accept 'discard' requests. > > RAID0 and LINEAR could be made to accept 'discard' if any > member device accepted 'discard'. Patches welcome. > > Other levels need md to know not to try to resync/recover regions that > have been discarded. See "non-sync bitmap" section of the recent > md roadmap. > > NeilBrown > -- > 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 > -- Roberto Spadim Spadim Technology / SPAEmpresarial -- 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
