Re: CephFs kernel client metadata caching

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,


On 10/13/2017 02:26 PM, Denes Dolhay wrote:
Hi,


Thank you for your fast response!


Is there a way -that You know of- to list these locks?
The only way I know of is dumping the MDS cache content. But I don't know exactly how to do it or how to analyse the content.

I write to the file with echo "foo" >> /mnt/ceph/...something... so if there is any locking, should not it be released after the append is done?

That's the capability for the file....but there are also capabilities for the directory itself. And capabilities are more complex than read/write locks.


The strange thing is, that this -increased traffic- stage went on for hours, tried many times, and after I stop the watch for ~5s (not tried different intervals) and restart it, the traffic is gone, and there is normal -I think some keepalive- comm between mds and client, two packets in ~5s (request, response)
I'm just guessing, but at that time both clients should have capabiltiies for the same directory. Maybe the client was checking whether it needs to change its capability?


As if the metadata cache would only be populated in a timer, (between 1s and 5s) which is never reached because of the repeated watch ls query .... just a blind shot in the dark...

You can increase the debugging level of the MDS. This should give you much more information about what's going on, what kind of requests are passed between the MDS and the clients etc.

Regards,
burkhard
_______________________________________________
ceph-users mailing list
ceph-users@xxxxxxxxxxxxxx
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com



[Index of Archives]     [Information on CEPH]     [Linux Filesystem Development]     [Ceph Development]     [Ceph Large]     [Ceph Dev]     [Linux USB Development]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [xfs]


  Powered by Linux