The OSD is able to use more than one core to do the work, so increasing the number of cores will increase throughput. However, if you care about latency then that is always tied to speed=frequency. If the question was "should I get 40GHz in 8 cores or in 16 cores" then the answer will always be "in 8 cores". However, higher freq. CPUs are much pricies than a lower ticking onec with more cores, so you will get a higher "throughput" for less $ if you scale the cores and not the frequency. If you need to run more OSDs on one host than the number of cores this gets a bit tricky, because of NUMA and linux scheduler that you should tune. If the number of OSDs is small enough I would always prefer the faster (frequency) CPU over a lower one. Jan > On 20 Jan 2016, at 13:01, Tomasz Kuzemko <tomasz.kuzemko@xxxxxxxxxxxx> wrote: > > Hi, > my team did some benchmarks in the past to answer this question. I don't > have results at hand, but conclusion was that it depends on how many > disks/OSDs you have in a single host: above 9 there was more benefit > from more cores than GHz (6-core 3.5GHz vs 10-core 2.4GHz AFAIR). > > -- > Tomasz Kuzemko > tomasz.kuzemko@xxxxxxxxxxxx > > On 20.01.2016 10:01, Götz Reinicke - IT Koordinator wrote: >> Hi folks, >> >> we plan to use more ssd OSDs in our first cluster layout instead of SAS >> osds. (more IO is needed than space) >> >> short question: What would influence the performance more? more Cores or >> more GHz/Core. >> >> Or is it as always: Depeds on the total of OSDs/nodes/repl-level/etc ... :) >> >> If needed, I can give some more detailed information on the layout. >> >> Thansk for feedback . Götz >> -- >> Götz Reinicke >> IT-Koordinator >> >> Tel. +49 7141 969 82420 >> E-Mail goetz.reinicke@xxxxxxxxxxxxxxx >> >> Filmakademie Baden-Württemberg GmbH >> Akademiehof 10 >> 71638 Ludwigsburg >> www.filmakademie.de >> >> Eintragung Amtsgericht Stuttgart HRB 205016 >> >> Vorsitzender des Aufsichtsrats: Jürgen Walter MdL >> Staatssekretär im Ministerium für Wissenschaft, >> Forschung und Kunst Baden-Württemberg >> >> Geschäftsführer: Prof. Thomas Schadt >> >> >> >> _______________________________________________ >> ceph-users mailing list >> ceph-users@xxxxxxxxxxxxxx >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> > > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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