Am 06.02.2014 16:24, schrieb Mark Nelson: > Hi Christian, can you tell me a little bit about how you are using Ceph and > what kind of IO you are doing?
Sure. We're using it almost exclusively for serving VM images that are accessed from Qemu's built-in RBD client. The VMs themselves perform a very wide range of I/O types, from servers that write mainly log files to ZEO database servers with nearly completely random I/O. Many VMs have slowly increasing storage utilization. A reason could be that the OSDs issue syncfs() calls and ext4 cuts FS extents from just what has been written so far. But I'm not sure about the exact pattern of OSD/filesystem interaction. HTH Christian -- Dipl.-Inf. Christian Kauhaus <>< · k...@gocept.com · systems administration gocept gmbh & co. kg · Forsterstraße 29 · 06112 Halle (Saale) · Germany http://gocept.com · tel +49 345 219401-11 Python, Pyramid, Plone, Zope · consulting, development, hosting, operations _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com