Hi all When setting a quota on a pool (or directory in Cephfs), is it the amount of client data written or the client data x number of replicas that counts toward the quota? Cheers A Sent from my iPhone
On Wed, 2021-03-17 at 08:26 +0000, Andrew Walker-Brown wrote:
When setting a quota on a pool (or directory in Cephfs), is it the amount of client data written or the client data x number of replicas that counts toward the quota?
It's the amount of data stored so independent of replication level. The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a th’ ann an Oilthigh Dhùn Èideann, clàraichte an Alba, àireamh clàraidh SC005336.
Hi Magnus, Thanks for the reply. Just to be certain (I’m having a slow day today), it’s the amount of data stored by the clients. As an example. a pool using 3 replicas and a quota 3TB : clients would be able to create up to 3TB of data and Ceph would use 9TB of raw storage? Cheers, A. Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10 From: Magnus HAGDORN<mailto:Magnus.Hagdorn@ed.ac.uk> Sent: 17 March 2021 08:59 To: ceph-users@ceph.io<mailto:ceph-users@ceph.io> Subject: [ceph-users] Re: Quick quota question On Wed, 2021-03-17 at 08:26 +0000, Andrew Walker-Brown wrote:
When setting a quota on a pool (or directory in Cephfs), is it the amount of client data written or the client data x number of replicas that counts toward the quota?
It's the amount of data stored so independent of replication level. The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a th’ ann an Oilthigh Dhùn Èideann, clàraichte an Alba, àireamh clàraidh SC005336. _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-leave@ceph.io
Hi, On 3/17/21 11:28 AM, Andrew Walker-Brown wrote:
Hi Magnus,
Thanks for the reply. Just to be certain (I’m having a slow day today), it’s the amount of data stored by the clients. As an example. a pool using 3 replicas and a quota 3TB : clients would be able to create up to 3TB of data and Ceph would use 9TB of raw storage?
In case of replicating pools with size=3, yes. Quotas are enforced by the cephfs clients (either kernel or fuse). And the clients do not know about the pool details (replicated vs. EC, sizes etc.). They only care for the primary OSD for the PGs (roughly speaking), since this OSD is handling the replication / EC stuff. Regards, burkhard
Thank you! Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10 From: Burkhard Linke<mailto:Burkhard.Linke@computational.bio.uni-giessen.de> Sent: 17 March 2021 10:32 To: ceph-users@ceph.io<mailto:ceph-users@ceph.io> Subject: [ceph-users] Re: Quick quota question Hi, On 3/17/21 11:28 AM, Andrew Walker-Brown wrote:
Hi Magnus,
Thanks for the reply. Just to be certain (I’m having a slow day today), it’s the amount of data stored by the clients. As an example. a pool using 3 replicas and a quota 3TB : clients would be able to create up to 3TB of data and Ceph would use 9TB of raw storage?
In case of replicating pools with size=3, yes. Quotas are enforced by the cephfs clients (either kernel or fuse). And the clients do not know about the pool details (replicated vs. EC, sizes etc.). They only care for the primary OSD for the PGs (roughly speaking), since this OSD is handling the replication / EC stuff. Regards, burkhard _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-leave@ceph.io
On 3/17/21 11:28 AM, Andrew Walker-Brown wrote:
Hi Magnus,
Thanks for the reply. Just to be certain (I’m having a slow day today), it’s the amount of data stored by the clients. As an example. a pool using 3 replicas and a quota 3TB : clients would be able to create up to 3TB of data and Ceph would use 9TB of raw storage?
Yes, but remember it's "client side security". So if the client does not play well nicely (malicious intent / buggy), it can ignore quotas. So make sure you have checks in place so you notice this. Of course depends on the threat model you have. FYI, Gr. Stefan
Ahh ok, good to know! Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10 From: Stefan Kooman<mailto:stefan@bit.nl> Sent: 17 March 2021 10:37 To: Andrew Walker-Brown<mailto:andrew_jbrown@hotmail.com>; Magnus HAGDORN<mailto:Magnus.Hagdorn@ed.ac.uk>; ceph-users@ceph.io<mailto:ceph-users@ceph.io> Subject: Re: [ceph-users] Re: Quick quota question On 3/17/21 11:28 AM, Andrew Walker-Brown wrote:
Hi Magnus,
Thanks for the reply. Just to be certain (I’m having a slow day today), it’s the amount of data stored by the clients. As an example. a pool using 3 replicas and a quota 3TB : clients would be able to create up to 3TB of data and Ceph would use 9TB of raw storage?
Yes, but remember it's "client side security". So if the client does not play well nicely (malicious intent / buggy), it can ignore quotas. So make sure you have checks in place so you notice this. Of course depends on the threat model you have. FYI, Gr. Stefan
participants (4)
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Andrew Walker-Brown
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Burkhard Linke
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Magnus HAGDORN
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Stefan Kooman