On Thu, 14 Mar 2013, Huang, Xiwei wrote: > Hi, all, > I noticed that CephFS fails to support Direct IO for blocks larger than 8MB, say: > sudo dd if=/dev/zero of=mnt/cephfs/foo bs=16M count=1 oflag=direct > dd: writing `mnt/cephfs/foo: Bad address > 1+0 records in > 0+0 records out > 0 bytes (0 B) copied, 0.213948 s, 0.0 kB/s > My version Ceph is 0.56.1. > ??I also found the bug has been already reported as Bug #2657. > Is this fixed in the new 0.58 version? I'm pretty sure this is a problem on the kernel client side of things, not the server side (which by default handles writes up to ~100MB or so). I suspect it isn't terribly difficult to fix, but hasn't been prioritized... sage
