Hello, On Wed, 11 Oct 2017 00:05:26 +0200 Jack wrote: > Hi, > > I would like some information about the following > > Let say I have a running cluster, with 4 OSDs: 2 SSDs, and 2 HDDs > My single pool has size=3, min_size=2 > > For a write-only pattern, I thought I would get SSDs performance level, > because the write would be acked as soon as min_size OSDs acked > > But I am right ? > You're the 2nd person in very recent times to come up with that wrong conclusion about min_size. All writes have to be ACKed, the only time where hybrid stuff helps is to accelerate reads. Which is something that people like me at least have very little interest in as the writes need to be fast. Christian > (the same setup could involve some high latency OSDs, in the case of > country-level cluster) > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > -- Christian Balzer Network/Systems Engineer chibi@xxxxxxx Rakuten Communications _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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