Hello, We are using Ceph as distributed block storage for our Openstack setup. Details: Ceph Version: 10.2.5 Openstack: Kilo We have 7 nodes, with each nodes configuration as below: HDD: 9 x 1.8T SSD: 3 x 447G CPU: Intel® Xeon® Processor E5-2620 v4 (8 Cores, 16 Threads) RAM: 64G Network: 2 x 10Gig Switch OS is on separate SSDs. Our use-case is to have Ceph as the back-end for our Openstack setup, mostly for Cinder and Glance and perhaps for Nova in the future. Keeping this in mind we tried using Bcache (1 : 3 :: SSD : HDD) and Cache Tier, but both seem to give similar results when benchmarked (tested using FIO)[1]. Now we're perplexed about which _caching mechanism_ to go with, and also curious about what would the ideal SSD:HDD ratio would be. Any suggestions/inputs regarding the same would be very welcome. [1]: https://software.intel.com/en-us/blogs/2013/10/25/measure-ceph-rbd-performance-in-a-quantitative-way-part-i -- Regards, Karthik Nayak _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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