On Wed, Nov 13, 2013 at 8:34 AM, Oliver Schulz <oschulz@xxxxxxxxxx> wrote: > Dear Ceph Experts, > > We're running a production Ceph cluster with Ceph Dumpling, > with Ubuntu 12.04.3 (kernel 3.8) on the cluster nodes and > all clients. We're mainly using CephFS (kernel) and RBD > (kernel and user-space/libvirt). > > Would you recommend to activate CRUSH_TUNABLES (1, not 2) for > our use case? I'd just like to make sure because crushtool > still says: "tunables are DANGEROUS and NOT YET RECOMMENDED". :-) I believe 3.8 is after CRUSH_TUNABLES v1 was implemented in the kernel, so it shouldn't hurt you to turn them on if you need them. (And the crush tool is just out of date; we should update that text!) However, if you aren't having distribution issues on your cluster I wouldn't bother — enabling them will shuffle your data around, and if you need to connect a client on an older kernel you'll be out of luck. -Greg Software Engineer #42 @ http://inktank.com | http://ceph.com _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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