In fact the autotuner does it itself every time it tunes the cache size:
https://github.com/ceph/ceph/blob/master/src/os/bluestore/BlueStore.cc#L3630
Mark
On 4/10/19 2:53 AM, Frédéric Nass wrote:
Hi everyone,
So if the kernel is able to reclaim those pages, is there still a
point in runni
Hi everyone,
So if the kernel is able to reclaim those pages, is there still a point
in running the heap release on a regular basis?
Regards,
Frédéric.
Le 09/04/2019 à 19:33, Olivier Bonvalet a écrit :
Good point, thanks !
By making memory pressure (by playing with vm.min_free_kbytes), memo
Good point, thanks !
By making memory pressure (by playing with vm.min_free_kbytes), memory
is freed by the kernel.
So I think I essentially need to update monitoring rules, to avoid
false positive.
Thanks, I continue to read your resources.
Le mardi 09 avril 2019 à 09:30 -0500, Mark Nelson a
My understanding is that basically the kernel is either unable or
uninterested (maybe due to lack of memory pressure?) in reclaiming the
memory . It's possible you might have better behavior if you set
/sys/kernel/mm/khugepaged/max_ptes_none to a low value (maybe 0) or
maybe disable transparen
Well, Dan seems to be right :
_tune_cache_size
target: 4294967296
heap: 6514409472
unmapped: 2267537408
mapped: 4246872064
old cache_size: 2845396873
new cache size: 2845397085
So we have 6GB in heap, but "only" 4GB mapped.
But "ceph tell osd.* heap release" shou
Thanks for the advice, we are using Debian 9 (stretch), with a custom
Linux kernel 4.14.
But "heap release" didn't help.
Le lundi 08 avril 2019 à 12:18 +0200, Dan van der Ster a écrit :
> Which OS are you using?
> With CentOS we find that the heap is not always automatically
> released. (You can
One of the difficulties with the osd_memory_target work is that we can't
tune based on the RSS memory usage of the process. Ultimately it's up to
the kernel to decide to reclaim memory and especially with transparent
huge pages it's tough to judge what the kernel is going to do even if
memory h
Which OS are you using?
With CentOS we find that the heap is not always automatically
released. (You can check the heap freelist with `ceph tell osd.0 heap
stats`).
As a workaround we run this hourly:
ceph tell mon.* heap release
ceph tell osd.* heap release
ceph tell mds.* heap release
-- Dan
O
Hi,
on a Luminous 12.2.11 deploiement, my bluestore OSD exceed the
osd_memory_target :
daevel-ob@ssdr712h:~$ ps auxw | grep ceph-osd
ceph3646 17.1 12.0 6828916 5893136 ? Ssl mars29 1903:42
/usr/bin/ceph-osd -f --cluster ceph --id 143 --setuser ceph --setgroup ceph
ceph3991 1
