In my experience 1GB cache could hold roughly 400k inodes.
_____________________________
From: Marc Roos <m.roos@xxxxxxxxxxxxxxxxx>
Sent: Monday, January 8, 2018 23:02
Subject: Re: MDS cache size limits
To: pdonnell <pdonnell@xxxxxxxxxx>, stefan <stefan@xxxxxx>
Cc: ceph-users <ceph-users@xxxxxxxxxxxxxx>
I guess the mds cache holds files, attributes etc but how many files
will the default "mds_cache_memory_limit": "1073741824" hold?
-----Original Message-----
From: Stefan Kooman [mailto:stefan@xxxxxx]
Sent: vrijdag 5 januari 2018 12:54
To: Patrick Donnelly
Cc: Ceph Users
Subject: Re: MDS cache size limits
Quoting Patrick Donnelly (pdonnell@xxxxxxxxxx):
>
> It's expected but not desired: http://tracker.ceph.com/issues/21402
>
> The memory usage tracking is off by a constant factor. I'd suggest
> just lowering the limit so it's about where it should be for your
> system.
Thanks for the info. Yeah, we did exactly that (observe and adjust
setting accordingly). Is this something worth mentioning in the
documentation? Escpecially when this "factor" is a constant? Over time
(with issue 21402 being worked on) things will change. Ceph operators
will want to make use of as much cache as possible without
overcommitting (MDS won't notice until there is no more memory left,
restart, and looses all its cache :/).
Gr. Stefan
--
| BIT BV http://www.bit.nl/ Kamer van Koophandel 09090351
| GPG: 0xD14839C6 +31 318 648 688 / info@xxxxxx
_______________________________________________
ceph-users mailing list
ceph-users@xxxxxxxxxxxxxx
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
_______________________________________________
ceph-users mailing list
ceph-users@xxxxxxxxxxxxxx
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
From: Marc Roos <m.roos@xxxxxxxxxxxxxxxxx>
Sent: Monday, January 8, 2018 23:02
Subject: Re: MDS cache size limits
To: pdonnell <pdonnell@xxxxxxxxxx>, stefan <stefan@xxxxxx>
Cc: ceph-users <ceph-users@xxxxxxxxxxxxxx>
I guess the mds cache holds files, attributes etc but how many files
will the default "mds_cache_memory_limit": "1073741824" hold?
-----Original Message-----
From: Stefan Kooman [mailto:stefan@xxxxxx]
Sent: vrijdag 5 januari 2018 12:54
To: Patrick Donnelly
Cc: Ceph Users
Subject: Re: MDS cache size limits
Quoting Patrick Donnelly (pdonnell@xxxxxxxxxx):
>
> It's expected but not desired: http://tracker.ceph.com/issues/21402
>
> The memory usage tracking is off by a constant factor. I'd suggest
> just lowering the limit so it's about where it should be for your
> system.
Thanks for the info. Yeah, we did exactly that (observe and adjust
setting accordingly). Is this something worth mentioning in the
documentation? Escpecially when this "factor" is a constant? Over time
(with issue 21402 being worked on) things will change. Ceph operators
will want to make use of as much cache as possible without
overcommitting (MDS won't notice until there is no more memory left,
restart, and looses all its cache :/).
Gr. Stefan
--
| BIT BV http://www.bit.nl/ Kamer van Koophandel 09090351
| GPG: 0xD14839C6 +31 318 648 688 / info@xxxxxx
_______________________________________________
ceph-users mailing list
ceph-users@xxxxxxxxxxxxxx
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
_______________________________________________
ceph-users mailing list
ceph-users@xxxxxxxxxxxxxx
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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