On Mon, Apr 5, 2021 at 1:33 PM Jeff Layton
<jlayton(a)redhat.com> wrote:
On Thu, 2021-04-01 at 11:04 +0200, Dan van der Ster wrote:
If one kernel mounts the
same cephfs several times (with different prefixes), we observed that
this is a unique client session. But does the ceph module globally
share a single copy of cluster metadata, e.g. osdmaps, or is that all
duplicated per session?
One copy per-cluster client, which should generally be shared between
mounts to the same cluster, provided that you're using similar-enough
mount options for the kernel to do that.
I suspect the problem is that if these are coming from mgr/volumes,
then each mount has a unique cephx user (and a client cap that locks
them into the exported directory), which means that the client
instances can't be shared.
Oof. You're probably right. In that case, you're sort of SoL since you
really do have to have a different client if the creds are different.
Still, it's hard to imagine that it's _that_ much overhead, even at 350
mounts, but I guess it depends on the amount of memory in the host.
--
Jeff Layton <jlayton(a)redhat.com>