On 06/18/2015 12:23 PM, Mark Nelson wrote:
I'm just guessing, but because your read performance is slow as well,
you may multiple issues going on. The Intel 530 being slow at O_DSYNC
writes is one of them, but it's possible there is something else too. If
I were in your position I think I'd try to beg/borrw/steal a single DC
S3700 or even 520 (despite it's presumed lack of safety) and just see
how a single OSD cluster using it does on your setup before replacing
everything.
After some (much!) more testing I finally have the results I'd expect! :)
Turns out we had two problems at once - first was the ssd (530 and the
problem mentioned) and the second was my testing scenario - the mounted
rbd is significantly slower than accessing it through librbd.
We've decided to go ahead and buy DC S3770 ssds.
So you were right all along. :)
Thanks for the help - much appreciated!
I have a last question though - is the kernel rbd implementation going
to be improved? or should we just forget about that and just use librbd?
Cheers,
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
