Hi, On 03/30/2016 05:45 PM, Graeme Donaldson wrote: > Hi, > > We're seeing very poor write performance on a cluster that was built > roughly a year ago. I am by no means an expert on OCFS2, nor the DRBD layer > that we have under it. We do have several clusters that are configured in > much the same way via our puppet infrastructure, yet this particular one > gives us write speeds around the 15 kilobyte/sec mark, where some of our > other clients do 55 megabytes/sec on similar hardware.
How did you perform the testing? It really matters. If you write a file on shared disk from one node, and read this file from another node, without, or with very little interval, the writing IO speed could decrease by ~20 times according my previous testing(just as a reference). It's a extremely bad situation for 2 nodes cluster, isn't? But it's incredible that in your case writing speed drop by >3000 times! > > I realise that this is all very vague, so for now I am just hoping for > general pointers on where to start in diagnosing this, from which I can do > more research and then hopefully revisit the thread with more detailed > questions and data. > > Some basic info to get started: > > O/S: Debian Wheezy > Kernel: Linux hostname 3.2.0-4-amd64 #1 SMP Debian 3.2.73-2+deb7u3 x86_64 > GNU/Linux > ocfs2-tools: 1.6.4-1+deb7u1 > 2 servers in the cluster. OCFS2 filesystem lives on a DRBD dual-primary > device, which itself is built on an LVM volume, whose VG lives on a RAID1 > pair of 1TB SATA HDDs. Could you firstly do test on LVM, then DRBD, and then OCFS2? Let's blame on them more fairly. Eric > > Happy to provide any other relevant information. > > Graeme. > > > > _______________________________________________ > Ocfs2-users mailing list > Ocfs2-users@oss.oracle.com > https://oss.oracle.com/mailman/listinfo/ocfs2-users > _______________________________________________ Ocfs2-users mailing list Ocfs2-users@oss.oracle.com https://oss.oracle.com/mailman/listinfo/ocfs2-users
