> But that still does not explain why you should get as low as 50 MB/s for > a single stream single client write when the backend can support direct > IO throughput of more than 700 MB/s. > > On the server, can you collect: > > # iostat -xcdh 2 > iostat.log.brickXX > > for the duration of the dd command ? > > and > > # strace -f -o stracelog.server -tt -T -e trace=write,writev -p > <glusterfsd.pid> > (again for the duration of the dd command) Hi John, A small change in the request. I hope you have not already spent time on this. The strace command should be: strace -f -o stracelog.server -tt -T -e trace=pwrite -p <glusterfsd.pid> Thanks, Pavan > > With the above, I want to measure the delay between the writes coming in > from the client. iostat will describe the IO scenario on the server. > Once the exercise is done, please attach the iostat.log.brickXX and > stracelog.server.