On 08/05/2014 02:48 PM, Gergely Horv?th wrote: > Thanks Wido for your comments. > > On 2014-07-30 15:39, Wido den Hollander wrote: >> Nothing specific, librados should give you what you need. Ceph is very >> concurrent, so if you write to different objects at the same time those >> I/Os will go in parallel. > > What if I try to write the same object? Two clients are sending a write > at the same time, but at a different offset. > The object doesn't get fully overwritten, but if the offsets and lengths overlap they will overwrite each other. Sometimes it might be better to use rados_append > Another interesting question that came up lately. Does Ceph support > "sparse objects"? > So if I create an object with one byte at the beginning, and then write > one byte with an offset of 64 megabytes, will it use only some bytes, or > take up the entire space (~64 MiB)? > It should be sparse. Only the written data will occupy space on the backing disk. Wido > -- > ?dv?zlettel / Best regards > > Horv?th Gergely | gergely.horvath at inepex.com > > IneTrack - Nyomk?vet?s egyszer?en | Inepex Kft. > ?gyf?lszolg?lat: support at inetrack.hu | +36 30 825 7646 | support.inetrack.hu > Web: www.inetrack.hu | nyomkovetes-blog.hu | facebook.com/inetrack > > Inepex - The White Label GPS fleet-tracking platform | www.inepex.com > _______________________________________________ > ceph-users mailing list > ceph-users at lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > -- Wido den Hollander 42on B.V. Ceph trainer and consultant Phone: +31 (0)20 700 9902 Skype: contact42on
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