Oleg, Very clear, thank you for the explanation, I misunderstood readahead. Yes the 1gb and 10gb file transfer tests was on par with NFS.
Our use case is typically compiling and find/grep through (30gb) amounts of source code so it seems we are stuck with small files. Andy On Fri, Jun 21, 2013 at 3:42 PM, Drokin, Oleg <oleg.dro...@intel.com> wrote: > Hello! > > On Jun 21, 2013, at 5:42 PM, Andrew Mast wrote: > > > Hello, I am new to Lustre and wanted to run a small simple small copy > test between 2 virtual machines from MDT/OST server to client's local disk. > > > I realize small file performance is never fast, but this seems > particularly slow considering the data is all buffered in memory with > little to no disk activity. > > > > RPC stats on the client shows only 1 RPC in flight at a time. max > inflight is set to 64. Is that expected behavior for a copy? > > Well, it seems you are reading from Lustre. Small files too. > So Lustre reads a single file at a time (I assume you copy with somehing > like cp - single threadedly), readahead does not come into play because > file size > is smaller than 1 RPC. > So before we are done with a single file, we cannot guess there'd be > another request to the next file. That's why you have only one RPC in > flight. > > Also Lustre metadata protocol is somewhat more heavy than NFS, which would > explain why it's slower than NFS. > Situation should improve once you start trying bigger files. > > Bye, > Oleg
_______________________________________________ Lustre-discuss mailing list Lustre-discuss@lists.lustre.org http://lists.lustre.org/mailman/listinfo/lustre-discuss