Hi, That's interesting -- yes on a lightly loaded cluster the metadata IO should be almost nil. You can debug what is happening using ceph daemonperf on the active MDS, e.g. https://pastebin.com/raw/n0iD8zXY (Use a wide terminal to show all the columns). Normally, lots of md io would indicate that the cache size is too small for the workload; but since you said the clients are pretty idle, this might not be the case for you. Cheers, Dan On Thu, Jul 8, 2021 at 9:36 AM Flemming Frandsen <dren.dk@xxxxxxxxx> wrote: > > We have a nautilus cluster where any metadata write operation is very slow. > > We're seeing very light load from clients, as reported by dumping ops in > flight, often it's zero. > > We're also seeing about 100 MB/s writes to the metadata pool, constantly, > for weeks on end, which seems excessive, as only 22GB is utilized. > > Should the writes to the metadata pool not quiet down when there's nothing > going on? > > Is there any way i can get information about why the MDSes are thrashing so > badly? > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx > To unsubscribe send an email to ceph-users-leave@xxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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