Hello, On Thu, 11 Jan 2018 11:42:53 -0600 Adam Tygart wrote: > Some people are doing hyperconverged ceph, colocating qemu > virtualization with ceph-osds. It is relevant for a decent subset of > people here. Therefore knowledge of the degree of performance > degradation is useful. > It was my understanding that meltdown can not reach the host kernel space from inside VMs, only other VMs would be at risk at the most. Spectre is a different beast, but again AFAIK there aren't any kernel patches for that yet. See for example: https://security.stackexchange.com/questions/176709/meltdown-and-virtual-machines The chuckles you're hearing are me with nearly all of our compute nodes still being AMD ones. ^o^ Christian > -- > Adam > > On Thu, Jan 11, 2018 at 11:38 AM, <ceph@xxxxxxxxxxxxxx> wrote: > > I don't understand how all of this is related to Ceph > > > > Ceph runs on a dedicated hardware, there is nothing there except Ceph, and > > the ceph daemons have already all power on ceph's data. > > And there is no random-code execution allowed on this node. > > > > Thus, spectre & meltdown are meaning-less for Ceph's node, and mitigations > > should be disabled > > > > Is this wrong ? > > > > > > On 01/11/2018 06:26 PM, Dan van der Ster wrote: > >> > >> Hi all, > >> > >> Is anyone getting useful results with your benchmarking? I've prepared > >> two test machines/pools and don't see any definitive slowdown with > >> patched kernels from CentOS [1]. > >> > >> I wonder if Ceph will be somewhat tolerant of these patches, similarly > >> to what's described here: > >> http://www.scylladb.com/2018/01/07/cost-of-avoiding-a-meltdown/ > >> > >> Cheers, Dan > >> > >> [1] Ceph v12.2.2, FileStore OSDs, kernels 3.10.0-693.11.6.el7.x86_64 > >> vs the ancient 3.10.0-327.18.2.el7.x86_64 > >> _______________________________________________ > >> 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 > -- 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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