maybe try to play with io scheduler ? maybe noop can help ? (I'm out of idea) ----- Mail original ----- De: "Stefan Priebe - Profihost AG" <s.priebe@xxxxxxxxxxxx> À: "Mark Nelson" <mark.nelson@xxxxxxxxxxx> Cc: "Alexandre DERUMIER" <aderumier@xxxxxxxxx>, "ceph-devel" <ceph-devel@xxxxxxxxxxxxxxx>, "Mark Kampe" <mark.kampe@xxxxxxxxxxx>, "Sébastien Han" <han.sebastien@xxxxxxxxx> Envoyé: Vendredi 23 Novembre 2012 14:24:26 Objet: Re: RBD fio Performance concerns Am 23.11.2012 14:18, schrieb Mark Nelson: > Agreed with Alexandre, try putting the journal on a raw partition. > That's pretty insane! What controller are you using again? Makes no difference. No Controller. Just using the SATA 3.0 onboard Ports for each SSD. fio directly on SSD gives me 45.000 rand 4k write iops and 270Mb/s seq write speed. So that's ok. Stefan > Mark > > On 11/23/2012 05:03 AM, Alexandre DERUMIER wrote: >> so correcly aligned... >> >> Maybe try to use journal directly on the full partition, without xfs ? >> >> >> ----- Mail original ----- >> >> De: "Stefan Priebe - Profihost AG" <s.priebe@xxxxxxxxxxxx> >> À: "Alexandre DERUMIER" <aderumier@xxxxxxxxx> >> Cc: "Mark Nelson" <mark.nelson@xxxxxxxxxxx>, "ceph-devel" >> <ceph-devel@xxxxxxxxxxxxxxx>, "Mark Kampe" <mark.kampe@xxxxxxxxxxx>, >> "Sébastien Han" <han.sebastien@xxxxxxxxx> >> Envoyé: Vendredi 23 Novembre 2012 11:49:10 >> Objet: Re: RBD fio Performance concerns >> >> Am 23.11.2012 11:47, schrieb Alexandre DERUMIER: >>>>> when i switch the journal to the OSD Disk seperate partiton on each >>>>> disk >>>>> (/dev/sdX1 for journal 1GB and /dev/sdX2 for OSD) i go down from >>>>> 23.000 >>>>> iops to 200 iops random 4k. >>> O_o , that's seem crazy... >>> Are you sure that your partitions are correctly aligned ? (starting >>> first partition at sector 2048 is best for ssd) >> >> Model: ATA INTEL SSDSC2CW24 (scsi) >> Disk /dev/sdb: 468862128s >> Sector size (logical/physical): 512B/512B >> Partition Table: gpt >> >> Number Start End Size File system Name Flags >> 1 2048s 2342911s 2340864s xfs pri >> 2 2342912s 468860927s 466518016s xfs pri >> >> Stefan >> > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
