Hi Ben, Thanks for the expert advice. On Fri, Aug 3, 2012 at 2:35 PM, Ben England <bengland at redhat.com> wrote: > 4. Re: kernel parameters for improving gluster writes on millions of small > writes (long) (Harry Mangalam) > > Harry, You are correct, Glusterfs throughput with small write transfer > sizes is a client-side problem, here are workarounds that at least some > applications could use. > Not to be impertinent nor snarky, but why is the gluster client written in this way and is that a high priority for fixing? It seems that caching/buffering is one of the great central truths of computer science in general. Is there a countering argument for not doing this? 1) NFS client is one workaround, since it buffers writes using the kernel > buffer cache. > Yes, I tried this and I find the same thing. One thing I am unclear about tho is whether you can set up and run 1 NFS server per gluster server node. ie my glusterfs runs on 4 servers - could I connect clients to each one using a round robin selection or other load/bandwidth balancing approach? I've read opinions that seem to support both yes and no. > > 2) If your app does not have a configurable I/O size, but it lets you > write to stdout, you can try piping your output to stdout and letting dd > aggregate your I/O to the filesystem for you. In this example we triple > single-thread write throughput for 4-KB I/O requests in this example. I agree again - I wrote up this for the gluster 'hints' <http://goo.gl/NyMXO> using gzip (other utilities seem to work as well, as do named pipes for handling more complex output options. > [nice examples deleted] > > 3) If your program is written in "C" and it uses stdio.h, you can probably > do setvbuf() "C" RTL call to increase buffer size to something greater than > 8 KB, which is the default in gcc-4.4. > Most of our users are not programmers and so this is not an option in most cases. > > http://en.cppreference.com/w/c/io/setvbuf > _______________________________________________ > Gluster-users mailing list > Gluster-users at gluster.org > http://gluster.org/cgi-bin/mailman/listinfo/gluster-users > -- Harry Mangalam - Research Computing, OIT, Rm 225 MSTB, UC Irvine [m/c 2225] / 92697 Google Voice Multiplexer: (949) 478-4487 415 South Circle View Dr, Irvine, CA, 92697 [shipping] MSTB Lat/Long: (33.642025,-117.844414) (paste into Google Maps) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://gluster.org/pipermail/gluster-users/attachments/20120803/ecf6bd29/attachment.htm>
