> -----Original Message----- > From: ceph-users [mailto:ceph-users-bounces@xxxxxxxxxxxxxx] On Behalf Of > Jacek Jarosiewicz > Sent: 20 August 2015 07:31 > To: Nick Fisk <nick@xxxxxxxxxx>; ceph-users@xxxxxxxx > Subject: Re: requests are blocked - problem > > On 08/19/2015 03:41 PM, Nick Fisk wrote: > > Although you may get some benefit from tweaking parameters, I suspect > you are nearer the performance ceiling for the current implementation of > the tiering code. Could you post all the variables you set for the tiering > including target_max_bytes and the dirty/full ratios. > > > > sure, all the parameters set are like this: > > hit_set_type bloom > hit_set_count 1 > hit_set_period 3600 > target_max_bytes 65498264640 > target_max_objects 1000000 > cache_target_full_ratio 0.95 > cache_min_flush_age 600 > cache_min_evict_age 1800 > cache_target_dirty_ratio 0.75 That pretty much looks ok to me, the only thing I can suggest is maybe to lower the full_ratio a bit. The full ratio is based on the percentage across the whole pool, but the actual eviction occurs at a percentage of a PG level. I think this may mean that in certain cases a PG may block whilist is evicts even though it appears the pool hasn't reached the full target. > > > > Since you are doing maildirs, which will have lots of small files, you might > also want to try making the object size of the RBD smaller. This will mean less > data is needed to be shifted on each promotion/flush. > > > > I'll try that - thanks! > > J > > -- > Jacek Jarosiewicz > Administrator Systemów Informatycznych > > ---------------------------------------------------------------------------------------- > SUPERMEDIA Sp. z o.o. z siedzibą w Warszawie ul. Senatorska 13/15, 00-075 > Warszawa Sąd Rejonowy dla m.st.Warszawy, XII Wydział Gospodarczy > Krajowego Rejestru Sądowego, nr KRS 0000029537; kapitał zakładowy > 42.756.000 zł > NIP: 957-05-49-503 > Adres korespondencyjny: ul. Jubilerska 10, 04-190 Warszawa > > ---------------------------------------------------------------------------------------- > SUPERMEDIA -> http://www.supermedia.pl > dostep do internetu - hosting - kolokacja - lacza - telefonia > _______________________________________________ > 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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