On Tue, 29 May 2012 11:30:27 +0200 Sebastian Riemer <sebastian.riemer@xxxxxxxxxxxxxxxx> wrote: > On 28/05/12 06:05, NeilBrown wrote: > > What do you mean by "doesn't work"? Returns errors? crashes? hangs? kills > > you cat? > > > > dd with oflag=direct returned an IO error. Odd. Updating mdadm shouldn't affect that. > > > It works for me. > > > > When I use 32K direct writes to a RAID1, both underlying RAID0 arrays see > > 64-sector writes. > > > > (when I do normal buffered writes I see 8-sector writes which seems odd, > > but clearly md/RAID1 is allowing large writes through) > > > > Now, I've updated mdadm to version 3.2.5 and it works like you've > described it. Thanks for your help! But the buffered IO is what matters. > 4k isn't enough there. Please inform me about changes which increase the > size in buffered IO. I'll have a look at this, too. I don't know. I'd have to dive into the code and look around and put a few printks in to see what is happening. NeilBrown
Attachment:
signature.asc
Description: PGP signature
