search for: randrepeat

Excellent description, thank you. With performance.write-behind-trickling-writes ON (default): ## 4k randwrite # fio --randrepeat=1 --ioengine=libaio --gtod_reduce=1 --name=test --filename=test --bs=4k --iodepth=32 --size=256MB --readwrite=randwrite test: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=32 fio-3.1 Starting 1 process Jobs: 1 (f=1): [w(1)][100.0%][r=0KiB/s,w=17...

On Tue, Mar 20, 2018 at 8:57 AM, Sam McLeod <mailinglists at smcleod.net> wrote: > Hi Raghavendra, > > > On 20 Mar 2018, at 1:55 pm, Raghavendra Gowdappa <rgowdapp at redhat.com> > wrote: > > Aggregating large number of small writes by write-behind into large writes > has been merged on master: > https://github.com/gluster/glusterfs/issues/364 > >

...me details about my setup: I am testing for-linus Chris''s branch I have one subvolume with 8 large files (10GB each). I am running two fio processes (one per file, so only 2 out of 8 files are involved) with 8 threads each like this: fio --thread --directory=/btrfs/subvol1 --rw=randwrite --randrepeat=1 --fadvise_hint=0 --fallocate=posix --size=1000m --filesize=10737418240 --bsrange=512b-64k --scramble_buffers=1 --nrfiles=1 --overwrite=1 --ioengine=sync --filename=file-1 --name=job0 --name=job1 --name=job2 --name=job3 --name=job4 --name=job5 --name=job6 --name=job7 The files are preallocated wit...

...entOS1 And install everything on the single vda disc with LVM (i use defaults in anaconda, but remove the large /home to prevent SSD beeing over used). After install and reboot log in to VM and yum install epel-release -y && yum install screen fio htop -y and then run disk test: fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 --name=test *--filename=test* --bs=4k --iodepth=64 --size=4G --readwrite=randrw --rwmixread=75 then *keep repeating *but *change the filename* attribute so it does not use the same blocks over and over again. In the beginning the performance is gr...

...ngle vda disc with LVM (i use defaults in > anaconda, but remove the large /home to prevent SSD beeing over used). > > After install and reboot log in to VM and > > yum install epel-release -y && yum install screen fio htop -y > > and then run disk test: > > fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 > --name=test *--filename=test* --bs=4k --iodepth=64 --size=4G > --readwrite=randrw --rwmixread=75 > > then *keep repeating *but *change the filename* attribute so it does not > use the same blocks over and over again. > > In the b...

...> defaults in anaconda, but remove the large /home to prevent SSD > beeing over used). > > After install and reboot log in to VM and > > yum install epel-release -y && yum install screen fio htop -y > > and then run disk test: > > fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 > --name=test *--filename=test* --bs=4k --iodepth=64 --size=4G > --readwrite=randrw --rwmixread=75 > > then *keep repeating *but *change the filename* attribute so it > does not use the same blocks over and over again. &g...

Hi Rob & Mihai, I wrote vhost-nvme patches on top of Christoph's NVMe target. vhost-nvme still uses mmio. So the guest OS can run unmodified NVMe driver. But the tests I have done didn't show competitive performance compared to virtio-blk/virtio-scsi. The bottleneck is in mmio. Your nvme vendor extension patches reduces greatly the number of MMIO writes. So I'd like to push it

Hi Rob & Mihai, I wrote vhost-nvme patches on top of Christoph's NVMe target. vhost-nvme still uses mmio. So the guest OS can run unmodified NVMe driver. But the tests I have done didn't show competitive performance compared to virtio-blk/virtio-scsi. The bottleneck is in mmio. Your nvme vendor extension patches reduces greatly the number of MMIO writes. So I'd like to push it