On Fri, Apr 27, 2012 at 01:02:08PM +0200, Christian Brunner wrote: > Am 24. April 2012 18:26 schrieb Sage Weil <sage@xxxxxxxxxxxx>: > > On Tue, 24 Apr 2012, Josef Bacik wrote: > >> On Fri, Apr 20, 2012 at 05:09:34PM +0200, Christian Brunner wrote: > >> > After running ceph on XFS for some time, I decided to try btrfs again. > >> > Performance with the current "for-linux-min" branch and big metadata > >> > is much better. The only problem (?) I'm still seeing is a warning > >> > that seems to occur from time to time: > > > > Actually, before you do that... we have a new tool, > > test_filestore_workloadgen, that generates a ceph-osd-like workload on the > > local file system. It's a subset of what a full OSD might do, but if > > we're lucky it will be sufficient to reproduce this issue. Something like > > > > test_filestore_workloadgen --osd-data /foo --osd-journal /bar > > > > will hopefully do the trick. > > > > Christian, maybe you can see if that is able to trigger this warning? > > You'll need to pull it from the current master branch; it wasn't in the > > last release. > > Trying to reproduce with test_filestore_workloadgen didn't work for > me. So here are some instructions on how to reproduce with a minimal > ceph setup. > > You will need a single system with two disks and a bit of memory. > > - Compile and install ceph (detailed instructions: > http://ceph.newdream.net/docs/master/ops/install/mkcephfs/) > > - For the test setup I've used two tmpfs files as journal devices. To > create these, do the following: > > # mkdir -p /ceph/temp > # mount -t tmpfs tmpfs /ceph/temp > # dd if=/dev/zero of=/ceph/temp/journal0 count=500 bs=1024k > # dd if=/dev/zero of=/ceph/temp/journal1 count=500 bs=1024k > > - Now you should create and mount btrfs. Here is what I did: > > # mkfs.btrfs -l 64k -n 64k /dev/sda > # mkfs.btrfs -l 64k -n 64k /dev/sdb > # mkdir /ceph/osd.000 > # mkdir /ceph/osd.001 > # mount -o noatime,space_cache,inode_cache,autodefrag /dev/sda /ceph/osd.000 > # mount -o noatime,space_cache,inode_cache,autodefrag /dev/sdb /ceph/osd.001 > > - Create /etc/ceph/ceph.conf similar to the attached ceph.conf. You > will probably have to change the btrfs devices and the hostname > (os39). > > - Create the ceph filesystems: > > # mkdir /ceph/mon > # mkcephfs -a -c /etc/ceph/ceph.conf > > - Start ceph (e.g. "service ceph start") > > - Now you should be able to use ceph - "ceph -s" will tell you about > the state of the ceph cluster. > > - "rbd create -size 100 testimg" will create an rbd image on the ceph cluster. > > - Compile my test with "gcc -o rbdtest rbdtest.c -lrbd" and run it > with "./rbdtest testimg". > > I can see the first btrfs_orphan_commit_root warning after an hour or > so... I hope that I've described all necessary steps. If there is a > problem just send me a note. > Well it's only taken me 2 weeks but I've finally git it all up and running, hopefully I'll reproduce. Thanks, Josef -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
