We have the model with 25 disks per node. We have just two 10G network interfaces per node. Does that not limit the thgouthput and hence the load on the CPUs? -Sreenath On 4/2/15, Alexandre DERUMIER <aderumier@xxxxxxxxx> wrote: > Hi, > >>>with HP SL4540 server? > > this model http://www8.hp.com/h20195/v2/GetDocument.aspx?docname=c04128155 > ? > > (60 drives ?) > > I think for a full ssd node, it'll be impossible to reach max performance, > you'll be cpu bound. > > > I think a small node with 6-8 ssd osd for 20cores should be ok. > > > ----- Mail original ----- > De: "Sreenath BH" <bhsreenath@xxxxxxxxx> > À: "Christian Balzer" <chibi@xxxxxxx> > Cc: "ceph-users" <ceph-users@xxxxxxxxxxxxxx> > Envoyé: Jeudi 2 Avril 2015 11:55:52 > Objet: Re: Cores/Memory/GHz recommendation for SSD based > OSD servers > > Thanks for the tips. > Could anyone share their experience building a SSD pool or a SSD cache > tier with HP SL4540 server? > > rgds, > Sreenath > > On 4/2/15, Christian Balzer <chibi@xxxxxxx> wrote: >> >> Hello, >> >> On Wed, 1 Apr 2015 18:40:10 +0530 Sreenath BH wrote: >> >>> Hi all, >>> >>> we are considering building all SSD OSD servers for RBD pool. >>> >> I'd advise you to spend significant time reading the various threads in >> this ML about SSD based pools. >> Both about the current shortcomings and limitations of SSD pools and which >> >> SSDs to (not) use. >> >>> Couple of questions: >>> >>> Does Ceph have any recommendation for number of cores/memory/ghz per >>> SSD drive, similar to what is usually followed for hard drives(1 >>> core/1 GB Ram/1Ghz speed)? >>> >> Note that that 1GHz core per OSD only applies with pure HDD OSDs, once a >> journal SSD enters the picture you're likely to want 2-3 times that. >> >> You probably don't want to try this with anything less than the >> upcoming Hammer release, but even with that the current rule for SSD based >> >> pools is "the fastest cores you can afford and as many as possible". >> And given the right loads, small write IOPS basically, you're probably >> still going to be CPU bound. >> >> RAM is the same as with HDD based OSDs, but given how much more RAM helps >> >> I would advise at least 2GB per OSD and as much as you can afford. >> >> Regards, >> >> Christian >>> thanks, >>> Sreenath >>> _______________________________________________ >>> ceph-users mailing list >>> ceph-users@xxxxxxxxxxxxxx >>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >>> >> >> >> -- >> Christian Balzer Network/Systems Engineer >> chibi@xxxxxxx Global OnLine Japan/Fusion Communications >> http://www.gol.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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