Hi,
On 1 Feb 2015 22:04, "Xu (Simon) Chen" wrote:
>
> Dan,
>
> I alway have noout set, so that single OSD failures won't trigger any
recovery immediately. When the OSD (or sometimes multiple OSDs on the same
server) comes back, I do see slow requests during backfilling, but probably
not thousands.
Dan,
I alway have noout set, so that single OSD failures won't trigger any
recovery immediately. When the OSD (or sometimes multiple OSDs on the same
server) comes back, I do see slow requests during backfilling, but probably
not thousands. When I added a brand new OSD into the cluster, for some
r
Hi,
When do you see thousands of slow requests during recovery... Does that
happen even with single OSD failures? You should be able to recover disks
without slow requests.
I always run with recovery op priority at the minimum 1. Tweaking the
number of max backfills did not change much during that
Hi Xu,
On 01.02.2015 21:39, Xu (Simon) Chen wrote:
> RBD doesn't work extremely well when ceph is recovering - it is common
> to see hundreds or a few thousands of blocked requests (>30s to
> finish). This translates high IO wait inside of VMs, and many
> applications don't deal with this well.
th
In my case, each object is 8MB (glance default for storing images on rbd
backend.) RBD doesn't work extremely well when ceph is recovering - it is
common to see hundreds or a few thousands of blocked requests (>30s to
finish). This translates high IO wait inside of VMs, and many applications
don't
Hi,
I don't know the general calculation, but last week we split a pool with 20
million tiny objects from 512 to 1024 pgs, on a cluster with 80 OSDs. IIRC
around 7 million objects needed to move, and it took around 13 hours to
finish. The bottleneck in our case was objects per second (limited to
ar
Hi folks,
I was running a ceph cluster with 33 OSDs. More recently, 33x6 new OSDs
hosted on 33 new servers were added, and I have finished balancing the data
and then marked the 33 old OSDs out.
As I have 6x as many OSDs, I am thinking of increasing pg_num of my largest
pool from 1k to at least 8
