> : We're currently co-locating our mons with the head node of our Hadoop
> : installation. That may be giving us some problems, we dont know yet, but
> : thus I'm speculation about moving them to dedicated hardware.
Would it be ok to run them on kvm VM’s - of course not backed by ceph?
Jesper
On 25 Nov 2018, at 15.17, Vitaliy Filippov wrote:
>
> All disks (HDDs and SSDs) have cache and may lose non-transactional writes
> that are in-flight. However, any adequate disk handles fsync's (i.e SATA
> FLUSH CACHE commands). So transactional writes should never be lost, and in
> Ceph ALL w
> On 24 Nov 2018, at 18.09, Anton Aleksandrov wrote
> We plan to have data on dedicate disk in each node and my question is about
> WAL/DB for Bluestore. How bad would it be to place it on system-consumer-SSD?
> How big risk is it, that everything will get "slower than using spinning HDD
> fo
On 14 Oct 2018, at 15.26, John Hearns wrote:
>
> This is a general question for the ceph list.
> Should Jesper be looking at these vm tunables?
> vm.dirty_ratio
> vm.dirty_centisecs
>
> What effect do they have when using Cephfs?
This situation is a read only, thus no dirty data in page cache.
