> Actually, we didn't change priority of discard command, so that it is still > synchronous IO for I/O scheduler, hence I/O interference will still exist if we > try to issue discard without IO aware ability. > Of course we can change the priority of discard command to lower, but potential > issue is that with ROW I/O scheduler in kernel or FTL, async I/O will handle > very slowly in heavy load scenario, if we are going to trigger sync write IO in > place in where we're doing async discard, we will face long latency. > Still I think it is worth to build the ability to issue async discard as a part > of discard policy and later we can adjust policy based on different scenario. > Thanks, Oh, I see. f2fs is sending discard requests as "sync" requests, I didn't know that. Right, I just though in case of CFQ I/O scheduler, but f2fs has to consider the other schedulers, but CFQ. Thanks, :)
