>>May be my default cfq slowdown? Yes ! (in your first mail you said that you use deadline scheduler ?)
cfq don't play well with a lof of current job. cfq + numjobs=10 : 10000 iops cfq + numjobs=1 : 25000 iops deadline + numjobs=1 : 25000 iops deadline + numjobs=10 : 25000 iops ----- Mail original ----- De: "Vasiliy Tolstov" <[email protected]> À: "aderumier" <[email protected]> Cc: "qemu-devel" <[email protected]> Envoyé: Mercredi 25 Novembre 2015 11:48:11 Objet: Re: [Qemu-devel] poor virtio-scsi performance (fio testing) 2015-11-25 13:27 GMT+03:00 Alexandre DERUMIER <[email protected]>: > I have tested with a raw file, qemu 2.4 + virtio-scsi (without iothread), I'm > around 25k iops > with an intel ssd 3500. (host cpu are xeon v3 3,1ghz) What scheduler you have on host system? May be my default cfq slowdown? -- Vasiliy Tolstov, e-mail: [email protected]
