Hello, re-tested, however also changed some more parameters than just the volume option due to reinstall: Ubuntu 14.04 -> CentOS 7 (*) Glusterfs 3.6.2 from RPM glusterfs-epel.repo vs. gluster-3.6 ppa Otherwise the test setup is the same. The results are: 3.6.2-CentOS7-cluster.ensure-durability-on: ~65-72 MiB/s 3.6.2-CentOS7-cluster.ensure-durability-off: ~86-89 MiB/s So the question from our side is now, what is exactly the threat that we have when using cluster.ensure-durability-off? Also I wonder which other tuning parameters you can recommend for a workload in which we _only_ have VM images (i.e. big files)? Cheers, Nico (*) Using CentOS 7, as we are interested in using libgfapi with qemu. Nico Schottelius [Thu, Feb 12, 2015 at 12:07:33AM +0100]: > Hello, > > switching from 3.4.2 to 3.6.2 reduces our average test performance dramatically. > > Our test setup: directly connected 1 GBit/s hosts setup with: > > rm -rf /home/gluster/.glusterfs/ > rm /home/gluster/* > setfattr -x trusted.glusterfs.volume-id /home/gluster/ > setfattr -x trusted.gfid /home/gluster/ > gluster volume create xfs-plain replica 2 transport tcp vmhost1-cluster1:/home/gluster vmhost2-cluster1:/home/gluster > gluster volume start xfs-plain > > Afterwards we run our near real world test > > mount -t glusterfs vmhost1-cluster1:/xfs-plain /mnt/gluster/ > while true; do dd if=redmine-from-ceph-20150204 of=/mnt/gluster/testvm bs=1M; rm /mnt/gluster/testvm; done > > The results are > > 3.4.2: ~71-72 MiB/s [ubuntu 14.04] > 3.6.2: ~59-64 MiB/s [gluster-3.6 ppa] > > We have removed 3.6.2 and re-installed 3.4.2 and can consistently reproduce > these numbers over hours of testing. > > Is there any configuration change that we need to incorporate to run > 3.6.2 faster or is this a known problem? > > Cheers, > > Nico > > -- > New PGP key: 659B 0D91 E86E 7E24 FD15 69D0 C729 21A1 293F 2D24 > _______________________________________________ > Gluster-users mailing list > Gluster-users@xxxxxxxxxxx > http://www.gluster.org/mailman/listinfo/gluster-users -- New PGP key: 659B 0D91 E86E 7E24 FD15 69D0 C729 21A1 293F 2D24 _______________________________________________ Gluster-users mailing list Gluster-users@xxxxxxxxxxx http://www.gluster.org/mailman/listinfo/gluster-users