> In Ceph/Libvirt docs only cachmodes writetrough and writeback are discussed. My clients's disks are all set to writeback in the libvirt client xml-definition. > > For a backup operation, I notice a severe lag on one of my VM's. Such a backup operation that takes 1 to 2 hours (on a same machine but) on local LVM storage, takes on a ceph storage 6 hours. Though I have to say that the cachemode on the local LVM storage is set on directsync. Writeback/writethrough also would affect writes only, so it should have quite little bearing on backup jobs, which usually are 99.99% read operations of various kinds. -- May the most significant bit of your life be positive. _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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