Hi, while running tests to collect data using LTTng, I was hitting the message throttle in ceph-osd, which is controlled by configuration option osd_map_message_max, default 100.
If I am not mistaken, then this throttle hits when more than 100 messages received via SimpleMessenger are not yet destructed, i.e. are still under processing within the affected ceph-osd daemon. I was running a fio test, random writes of 4 KByte with 16 parallel IO's. The storage cluster consists of 12 osds on 3 storage nodes, replication level 3. I wonder why I hit that message throttle with my load profile: the 16 parallel IO's should at most generate 48 data messages and also 48 acknowledges across the cluster - so I would not expect anything even close to a 100 message limit on a single osd in my cluster. Did anybody else experience such issues? Are there other throttle values which I should look at? Regards Andreas Bluemle -- Andreas Bluemle mailto:[email protected] ITXperts GmbH http://www.itxperts.de Balanstrasse 73, Geb. 08 Phone: (+49) 89 89044917 D-81541 Muenchen (Germany) Fax: (+49) 89 89044910 Company details: http://www.itxperts.de/imprint.htm -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
