| Proxmox 4.0 will allow to enable|disable 1 iothread by disk. Alexandre, Useful option! In proxmox 3.4 will it be possible to add at least in the configuration file? Or it entails a change in the source code KVM? Thanks.
2015-06-22 11:54 GMT+03:00 Alexandre DERUMIER <aderum...@odiso.com>: > >>It is already possible to do in proxmox 3.4 (with the latest updates > qemu-kvm 2.2.x). But it is necessary to register in the conf file > iothread:1. For single drives the ambiguous behavior of productivity. > > Yes and no ;) > > Currently in proxmox 3.4, iothread:1 generate only 1 iothread for all > disks. > > So, you'll have a small extra boost, but it'll not scale with multiple > disks. > > Proxmox 4.0 will allow to enable|disable 1 iothread by disk. > > > >>Does it also help for single disks or only multiple disks? > > Iothread can also help for single disk, because by default qemu use a main > thread for disk but also other things(don't remember what exactly) > > > > > ----- Mail original ----- > De: "Irek Fasikhov" <malm...@gmail.com> > À: "Stefan Priebe" <s.pri...@profihost.ag> > Cc: "aderumier" <aderum...@odiso.com>, "pushpesh sharma" < > pushpesh....@gmail.com>, "Somnath Roy" <somnath....@sandisk.com>, > "ceph-devel" <ceph-de...@vger.kernel.org>, "ceph-users" < > ceph-users@lists.ceph.com> > Envoyé: Lundi 22 Juin 2015 09:22:13 > Objet: Re: rbd_cache, limiting read on high iops around 40k > > It is already possible to do in proxmox 3.4 (with the latest updates > qemu-kvm 2.2.x). But it is necessary to register in the conf file > iothread:1. For single drives the ambiguous behavior of productivity. > > 2015-06-22 10:12 GMT+03:00 Stefan Priebe - Profihost AG < > s.pri...@profihost.ag > : > > > > Am 22.06.2015 um 09:08 schrieb Alexandre DERUMIER < aderum...@odiso.com >: > > >>> Just an update, there seems to be no proper way to pass iothread > >>> parameter from openstack-nova (not at least in Juno release). So a > >>> default single iothread per VM is what all we have. So in conclusion a > >>> nova instance max iops on ceph rbd will be limited to 30-40K. > > > > Thanks for the update. > > > > For proxmox users, > > > > I have added iothread option to gui for proxmox 4.0 > > Can we make iothread the default? Does it also help for single disks or > only multiple disks? > > > and added jemalloc as default memory allocator > > > > > > I have also send a jemmaloc patch to qemu dev mailing > > https://lists.gnu.org/archive/html/qemu-devel/2015-06/msg05265.html > > > > (Help is welcome to push it in qemu upstream ! ) > > > > > > > > ----- Mail original ----- > > De: "pushpesh sharma" < pushpesh....@gmail.com > > > À: "aderumier" < aderum...@odiso.com > > > Cc: "Somnath Roy" < somnath....@sandisk.com >, "Irek Fasikhov" < > malm...@gmail.com >, "ceph-devel" < ceph-de...@vger.kernel.org >, > "ceph-users" < ceph-users@lists.ceph.com > > > Envoyé: Lundi 22 Juin 2015 07:58:47 > > Objet: Re: rbd_cache, limiting read on high iops around 40k > > > > Just an update, there seems to be no proper way to pass iothread > > parameter from openstack-nova (not at least in Juno release). So a > > default single iothread per VM is what all we have. So in conclusion a > > nova instance max iops on ceph rbd will be limited to 30-40K. > > > > On Tue, Jun 16, 2015 at 10:08 PM, Alexandre DERUMIER > > < aderum...@odiso.com > wrote: > >> Hi, > >> > >> some news about qemu with tcmalloc vs jemmaloc. > >> > >> I'm testing with multiple disks (with iothreads) in 1 qemu guest. > >> > >> And if tcmalloc is a little faster than jemmaloc, > >> > >> I have hit a lot of time the > tcmalloc::ThreadCache::ReleaseToCentralCache bug. > >> > >> increasing TCMALLOC_MAX_TOTAL_THREAD_CACHE_BYTES, don't help. > >> > >> > >> with multiple disk, I'm around 200k iops with tcmalloc (before hitting > the bug) and 350kiops with jemmaloc. > >> > >> The problem is that when I hit malloc bug, I'm around 4000-10000 iops, > and only way to fix is is to restart qemu ... > >> > >> > >> > >> ----- Mail original ----- > >> De: "pushpesh sharma" < pushpesh....@gmail.com > > >> À: "aderumier" < aderum...@odiso.com > > >> Cc: "Somnath Roy" < somnath....@sandisk.com >, "Irek Fasikhov" < > malm...@gmail.com >, "ceph-devel" < ceph-de...@vger.kernel.org >, > "ceph-users" < ceph-users@lists.ceph.com > > >> Envoyé: Vendredi 12 Juin 2015 08:58:21 > >> Objet: Re: rbd_cache, limiting read on high iops around 40k > >> > >> Thanks, posted the question in openstack list. Hopefully will get some > >> expert opinion. > >> > >> On Fri, Jun 12, 2015 at 11:33 AM, Alexandre DERUMIER > >> < aderum...@odiso.com > wrote: > >>> Hi, > >>> > >>> here a libvirt xml sample from libvirt src > >>> > >>> (you need to define <iothreads> number, then assign then in disks). > >>> > >>> I don't use openstack, so I really don't known how it's working with > it. > >>> > >>> > >>> <domain type='qemu'> > >>> <name>QEMUGuest1</name> > >>> <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid> > >>> <memory unit='KiB'>219136</memory> > >>> <currentMemory unit='KiB'>219136</currentMemory> > >>> <vcpu placement='static'>2</vcpu> > >>> <iothreads>2</iothreads> > >>> <os> > >>> <type arch='i686' machine='pc'>hvm</type> > >>> <boot dev='hd'/> > >>> </os> > >>> <clock offset='utc'/> > >>> <on_poweroff>destroy</on_poweroff> > >>> <on_reboot>restart</on_reboot> > >>> <on_crash>destroy</on_crash> > >>> <devices> > >>> <emulator>/usr/bin/qemu</emulator> > >>> <disk type='file' device='disk'> > >>> <driver name='qemu' type='raw' iothread='1'/> > >>> <source file='/var/lib/libvirt/images/iothrtest1.img'/> > >>> <target dev='vdb' bus='virtio'/> > >>> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' > function='0x0'/> > >>> </disk> > >>> <disk type='file' device='disk'> > >>> <driver name='qemu' type='raw' iothread='2'/> > >>> <source file='/var/lib/libvirt/images/iothrtest2.img'/> > >>> <target dev='vdc' bus='virtio'/> > >>> </disk> > >>> <controller type='usb' index='0'/> > >>> <controller type='ide' index='0'/> > >>> <controller type='pci' index='0' model='pci-root'/> > >>> <memballoon model='none'/> > >>> </devices> > >>> </domain> > >>> > >>> > >>> ----- Mail original ----- > >>> De: "pushpesh sharma" < pushpesh....@gmail.com > > >>> À: "aderumier" < aderum...@odiso.com > > >>> Cc: "Somnath Roy" < somnath....@sandisk.com >, "Irek Fasikhov" < > malm...@gmail.com >, "ceph-devel" < ceph-de...@vger.kernel.org >, > "ceph-users" < ceph-users@lists.ceph.com > > >>> Envoyé: Vendredi 12 Juin 2015 07:52:41 > >>> Objet: Re: rbd_cache, limiting read on high iops around 40k > >>> > >>> Hi Alexandre, > >>> > >>> I agree with your rational, of one iothread per disk. CPU consumed in > >>> IOwait is pretty high in each VM. But I am not finding a way to set > >>> the same on a nova instance. I am using openstack Juno with QEMU+KVM. > >>> As per libvirt documentation for setting iothreads, I can edit > >>> domain.xml directly and achieve the same effect. However in as in > >>> openstack env domain xml is created by nova with some additional > >>> metadata, so editing the domain xml using 'virsh edit' does not seems > >>> to work(I agree, it is not a very cloud way of doing things, but a > >>> hack). Changes made there vanish after saving them, due to reason > >>> libvirt validation fails on the same. > >>> > >>> #virsh dumpxml instance-000000c5 > vm.xml > >>> #virt-xml-validate vm.xml > >>> Relax-NG validity error : Extra element cpu in interleave > >>> vm.xml:1: element domain: Relax-NG validity error : Element domain > >>> failed to validate content > >>> vm.xml fails to validate > >>> > >>> Second approach I took was to setting QoS in volumes types. But there > >>> is no option to set iothreads per volume, there are parameter realted > >>> to max_read/wrirte ops/bytes. > >>> > >>> Thirdly, editing Nova flavor and proving extra specs like > >>> hw:cpu_socket/thread/core, can change guest CPU topology however again > >>> no way to set iothread. It does accept hw_disk_iothreads(no type check > >>> in place, i believe ), but can not pass the same in domain.xml. > >>> > >>> Could you suggest me a way to set the same. > >>> > >>> -Pushpesh > >>> > >>> On Wed, Jun 10, 2015 at 12:59 PM, Alexandre DERUMIER > >>> < aderum...@odiso.com > wrote: > >>>>>> I need to try out the performance on qemu soon and may come back to > you if I need some qemu setting trick :-) > >>>> > >>>> Sure no problem. > >>>> > >>>> (BTW, I can reach around 200k iops in 1 qemu vm with 5 virtio disks > with 1 iothread by disk) > >>>> > >>>> > >>>> ----- Mail original ----- > >>>> De: "Somnath Roy" < somnath....@sandisk.com > > >>>> À: "aderumier" < aderum...@odiso.com >, "Irek Fasikhov" < > malm...@gmail.com > > >>>> Cc: "ceph-devel" < ceph-de...@vger.kernel.org >, "pushpesh sharma" < > pushpesh....@gmail.com >, "ceph-users" < ceph-users@lists.ceph.com > > >>>> Envoyé: Mercredi 10 Juin 2015 09:06:32 > >>>> Objet: RE: rbd_cache, limiting read on high iops around 40k > >>>> > >>>> Hi Alexandre, > >>>> Thanks for sharing the data. > >>>> I need to try out the performance on qemu soon and may come back to > you if I need some qemu setting trick :-) > >>>> > >>>> Regards > >>>> Somnath > >>>> > >>>> -----Original Message----- > >>>> From: ceph-users [mailto: ceph-users-boun...@lists.ceph.com ] On > Behalf Of Alexandre DERUMIER > >>>> Sent: Tuesday, June 09, 2015 10:42 PM > >>>> To: Irek Fasikhov > >>>> Cc: ceph-devel; pushpesh sharma; ceph-users > >>>> Subject: Re: [ceph-users] rbd_cache, limiting read on high iops > around 40k > >>>> > >>>>>> Very good work! > >>>>>> Do you have a rpm-file? > >>>>>> Thanks. > >>>> no sorry, I'm have compiled it manually (and I'm using debian jessie > as client) > >>>> > >>>> > >>>> > >>>> ----- Mail original ----- > >>>> De: "Irek Fasikhov" < malm...@gmail.com > > >>>> À: "aderumier" < aderum...@odiso.com > > >>>> Cc: "Robert LeBlanc" < rob...@leblancnet.us >, "ceph-devel" < > ceph-de...@vger.kernel.org >, "pushpesh sharma" < pushpesh....@gmail.com > >, "ceph-users" < ceph-users@lists.ceph.com > > >>>> Envoyé: Mercredi 10 Juin 2015 07:21:42 > >>>> Objet: Re: [ceph-users] rbd_cache, limiting read on high iops around > 40k > >>>> > >>>> Hi, Alexandre. > >>>> > >>>> Very good work! > >>>> Do you have a rpm-file? > >>>> Thanks. > >>>> > >>>> 2015-06-10 7:10 GMT+03:00 Alexandre DERUMIER < aderum...@odiso.com > > : > >>>> > >>>> > >>>> Hi, > >>>> > >>>> I have tested qemu with last tcmalloc 2.4, and the improvement is > huge with iothread: 50k iops (+45%) ! > >>>> > >>>> > >>>> > >>>> qemu : no iothread : glibc : iops=33395 qemu : no-iothread : tcmalloc > (2.2.1) : iops=34516 (+3%) qemu : no-iothread : jemmaloc : iops=42226 > (+26%) qemu : no-iothread : tcmalloc (2.4) : iops=35974 (+7%) > >>>> > >>>> > >>>> qemu : iothread : glibc : iops=34516 > >>>> qemu : iothread : tcmalloc : iops=38676 (+12%) qemu : iothread : > jemmaloc : iops=28023 (-19%) qemu : iothread : tcmalloc (2.4) : iops=50276 > (+45%) > >>>> > >>>> > >>>> > >>>> > >>>> > >>>> qemu : iothread : tcmalloc (2.4) : iops=50276 (+45%) > >>>> ------------------------------------------------------ > >>>> rbd_iodepth32-test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, > ioengine=libaio, iodepth=32 > >>>> fio-2.1.11 > >>>> Starting 1 process > >>>> Jobs: 1 (f=1): [r(1)] [100.0% done] [214.7MB/0KB/0KB /s] [54.1K/0/0 > iops] [eta 00m:00s] > >>>> rbd_iodepth32-test: (groupid=0, jobs=1): err= 0: pid=894: Wed Jun 10 > 05:54:24 2015 read : io=5120.0MB, bw=201108KB/s, iops=50276, runt= > 26070msec slat (usec): min=1, max=1136, avg= 3.54, stdev= 3.58 clat (usec): > min=128, max=6262, avg=631.41, stdev=197.71 lat (usec): min=149, max=6265, > avg=635.27, stdev=197.40 clat percentiles (usec): > >>>> | 1.00th=[ 318], 5.00th=[ 378], 10.00th=[ 418], 20.00th=[ 474], > >>>> | 30.00th=[ 516], 40.00th=[ 564], 50.00th=[ 612], 60.00th=[ 652], > >>>> | 70.00th=[ 700], 80.00th=[ 756], 90.00th=[ 860], 95.00th=[ 980], > >>>> | 99.00th=[ 1272], 99.50th=[ 1384], 99.90th=[ 1688], 99.95th=[ 1896], > >>>> | 99.99th=[ 3760] > >>>> bw (KB /s): min=145608, max=249688, per=100.00%, avg=201108.00, > stdev=21718.87 lat (usec) : 250=0.04%, 500=25.84%, 750=53.00%, 1000=16.63% > lat (msec) : 2=4.46%, 4=0.03%, 10=0.01% cpu : usr=9.73%, sys=24.93%, > ctx=66417, majf=0, minf=38 IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, > 16=0.1%, 32=100.0%, >=64=0.0% submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, > 32=0.0%, 64=0.0%, >=64=0.0% complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, > 32=0.1%, 64=0.0%, >=64=0.0% issued : total=r=1310720/w=0/d=0, > short=r=0/w=0/d=0 latency : target=0, window=0, percentile=100.00%, depth=32 > >>>> > >>>> Run status group 0 (all jobs): > >>>> READ: io=5120.0MB, aggrb=201107KB/s, minb=201107KB/s, > maxb=201107KB/s, mint=26070msec, maxt=26070msec > >>>> > >>>> Disk stats (read/write): > >>>> vdb: ios=1302555/0, merge=0/0, ticks=715176/0, in_queue=714840, > util=99.73% > >>>> > >>>> > >>>> > >>>> > >>>> > >>>> > >>>> rbd_iodepth32-test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, > ioengine=libaio, iodepth=32 > >>>> fio-2.1.11 > >>>> Starting 1 process > >>>> Jobs: 1 (f=1): [r(1)] [100.0% done] [158.7MB/0KB/0KB /s] [40.6K/0/0 > iops] [eta 00m:00s] > >>>> rbd_iodepth32-test: (groupid=0, jobs=1): err= 0: pid=889: Wed Jun 10 > 06:05:06 2015 read : io=5120.0MB, bw=143897KB/s, iops=35974, runt= > 36435msec slat (usec): min=1, max=710, avg= 3.31, stdev= 3.35 clat (usec): > min=191, max=4740, avg=884.66, stdev=315.65 lat (usec): min=289, max=4743, > avg=888.31, stdev=315.51 clat percentiles (usec): > >>>> | 1.00th=[ 462], 5.00th=[ 516], 10.00th=[ 548], 20.00th=[ 596], > >>>> | 30.00th=[ 652], 40.00th=[ 764], 50.00th=[ 868], 60.00th=[ 940], > >>>> | 70.00th=[ 1004], 80.00th=[ 1096], 90.00th=[ 1256], 95.00th=[ 1416], > >>>> | 99.00th=[ 2024], 99.50th=[ 2224], 99.90th=[ 2544], 99.95th=[ 2640], > >>>> | 99.99th=[ 3632] > >>>> bw (KB /s): min=98352, max=177328, per=99.91%, avg=143772.11, > stdev=21782.39 lat (usec) : 250=0.01%, 500=3.48%, 750=35.69%, 1000=30.01% > lat (msec) : 2=29.74%, 4=1.07%, 10=0.01% cpu : usr=7.10%, sys=16.90%, > ctx=54855, majf=0, minf=38 IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, > 16=0.1%, 32=100.0%, >=64=0.0% submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, > 32=0.0%, 64=0.0%, >=64=0.0% complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, > 32=0.1%, 64=0.0%, >=64=0.0% issued : total=r=1310720/w=0/d=0, > short=r=0/w=0/d=0 latency : target=0, window=0, percentile=100.00%, depth=32 > >>>> > >>>> Run status group 0 (all jobs): > >>>> READ: io=5120.0MB, aggrb=143896KB/s, minb=143896KB/s, > maxb=143896KB/s, mint=36435msec, maxt=36435msec > >>>> > >>>> Disk stats (read/write): > >>>> vdb: ios=1301357/0, merge=0/0, ticks=1033036/0, in_queue=1032716, > util=99.85% > >>>> > >>>> > >>>> ----- Mail original ----- > >>>> De: "aderumier" < aderum...@odiso.com > > >>>> À: "Robert LeBlanc" < rob...@leblancnet.us > > >>>> Cc: "Mark Nelson" < mnel...@redhat.com >, "ceph-devel" < > ceph-de...@vger.kernel.org >, "pushpesh sharma" < pushpesh....@gmail.com > >, "ceph-users" < ceph-users@lists.ceph.com > > >>>> Envoyé: Mardi 9 Juin 2015 18:47:27 > >>>> Objet: Re: [ceph-users] rbd_cache, limiting read on high iops around > 40k > >>>> > >>>> Hi Robert, > >>>> > >>>>>> What I found was that Ceph OSDs performed well with either tcmalloc > or > >>>>>> jemalloc (except when RocksDB was built with jemalloc instead of > >>>>>> tcmalloc, I'm still working to dig into why that might be the case). > >>>> yes,from my test, for osd tcmalloc is a little faster (but very > little) than jemalloc. > >>>> > >>>> > >>>> > >>>>>> However, I found that tcmalloc with QEMU/KVM was very detrimental to > >>>>>> small I/O, but provided huge gains in I/O >=1MB. Jemalloc was much > >>>>>> better for QEMU/KVM in the tests that we ran. [1] > >>>> > >>>> > >>>> Just have done qemu test (4k randread - rbd_cache=off), I don't see > speed regression with tcmalloc. > >>>> with qemu iothread, tcmalloc have a speed increase over glib > >>>> with qemu iothread, jemalloc have a speed decrease > >>>> > >>>> without iothread, jemalloc have a big speed increase > >>>> > >>>> this is with > >>>> -qemu 2.3 > >>>> -tcmalloc 2.2.1 > >>>> -jemmaloc 3.6 > >>>> -libc6 2.19 > >>>> > >>>> > >>>> qemu : no iothread : glibc : iops=33395 > >>>> qemu : no-iothread : tcmalloc : iops=34516 (+3%) > >>>> qemu : no-iothread : jemmaloc : iops=42226 (+26%) > >>>> > >>>> qemu : iothread : glibc : iops=34516 > >>>> qemu : iothread : tcmalloc : iops=38676 (+12%) > >>>> qemu : iothread : jemmaloc : iops=28023 (-19%) > >>>> > >>>> > >>>> (The benefit of iothreads is that we can scale with more disks in 1vm) > >>>> > >>>> > >>>> fio results: > >>>> ------------ > >>>> > >>>> qemu : iothread : tcmalloc : iops=38676 > >>>> ----------------------------------------- > >>>> rbd_iodepth32-test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, > ioengine=libaio, iodepth=32 > >>>> fio-2.1.11 > >>>> Starting 1 process > >>>> Jobs: 1 (f=0): [r(1)] [100.0% done] [123.5MB/0KB/0KB /s] [31.6K/0/0 > iops] [eta 00m:00s] > >>>> rbd_iodepth32-test: (groupid=0, jobs=1): err= 0: pid=1265: Tue Jun 9 > 18:16:53 2015 > >>>> read : io=5120.0MB, bw=154707KB/s, iops=38676, runt= 33889msec > >>>> slat (usec): min=1, max=715, avg= 3.63, stdev= 3.42 > >>>> clat (usec): min=152, max=5736, avg=822.12, stdev=289.34 > >>>> lat (usec): min=231, max=5740, avg=826.10, stdev=289.08 > >>>> clat percentiles (usec): > >>>> | 1.00th=[ 402], 5.00th=[ 466], 10.00th=[ 510], 20.00th=[ 572], > >>>> | 30.00th=[ 636], 40.00th=[ 716], 50.00th=[ 780], 60.00th=[ 852], > >>>> | 70.00th=[ 932], 80.00th=[ 1020], 90.00th=[ 1160], 95.00th=[ 1352], > >>>> | 99.00th=[ 1800], 99.50th=[ 1944], 99.90th=[ 2256], 99.95th=[ 2448], > >>>> | 99.99th=[ 3888] > >>>> bw (KB /s): min=123888, max=198584, per=100.00%, avg=154824.40, > stdev=16978.03 > >>>> lat (usec) : 250=0.01%, 500=8.91%, 750=36.44%, 1000=32.63% > >>>> lat (msec) : 2=21.65%, 4=0.37%, 10=0.01% > >>>> cpu : usr=8.29%, sys=19.76%, ctx=55882, majf=0, minf=39 > >>>> IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, > >=64=0.0% > >>>> submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > >>>> complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, > >=64=0.0% > >>>> issued : total=r=1310720/w=0/d=0, short=r=0/w=0/d=0 > >>>> latency : target=0, window=0, percentile=100.00%, depth=32 > >>>> > >>>> Run status group 0 (all jobs): > >>>> READ: io=5120.0MB, aggrb=154707KB/s, minb=154707KB/s, > maxb=154707KB/s, mint=33889msec, maxt=33889msec > >>>> > >>>> Disk stats (read/write): > >>>> vdb: ios=1302739/0, merge=0/0, ticks=934444/0, in_queue=934096, > util=99.77% > >>>> > >>>> > >>>> > >>>> qemu : no-iothread : tcmalloc : iops=34516 > >>>> --------------------------------------------- > >>>> Jobs: 1 (f=1): [r(1)] [100.0% done] [163.2MB/0KB/0KB /s] [41.8K/0/0 > iops] [eta 00m:00s] > >>>> rbd_iodepth32-test: (groupid=0, jobs=1): err= 0: pid=896: Tue Jun 9 > 18:19:08 2015 > >>>> read : io=5120.0MB, bw=138065KB/s, iops=34516, runt= 37974msec > >>>> slat (usec): min=1, max=708, avg= 3.98, stdev= 3.57 > >>>> clat (usec): min=208, max=11858, avg=921.43, stdev=333.61 > >>>> lat (usec): min=266, max=11862, avg=925.77, stdev=333.40 > >>>> clat percentiles (usec): > >>>> | 1.00th=[ 434], 5.00th=[ 510], 10.00th=[ 564], 20.00th=[ 652], > >>>> | 30.00th=[ 732], 40.00th=[ 812], 50.00th=[ 876], 60.00th=[ 940], > >>>> | 70.00th=[ 1020], 80.00th=[ 1112], 90.00th=[ 1320], 95.00th=[ 1576], > >>>> | 99.00th=[ 1992], 99.50th=[ 2128], 99.90th=[ 2736], 99.95th=[ 3248], > >>>> | 99.99th=[ 4320] > >>>> bw (KB /s): min=77312, max=185576, per=99.74%, avg=137709.88, > stdev=16883.77 > >>>> lat (usec) : 250=0.01%, 500=4.36%, 750=27.61%, 1000=35.60% > >>>> lat (msec) : 2=31.49%, 4=0.92%, 10=0.02%, 20=0.01% > >>>> cpu : usr=7.19%, sys=19.52%, ctx=55903, majf=0, minf=38 > >>>> IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, > >=64=0.0% > >>>> submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > >>>> complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, > >=64=0.0% > >>>> issued : total=r=1310720/w=0/d=0, short=r=0/w=0/d=0 > >>>> latency : target=0, window=0, percentile=100.00%, depth=32 > >>>> > >>>> Run status group 0 (all jobs): > >>>> READ: io=5120.0MB, aggrb=138064KB/s, minb=138064KB/s, > maxb=138064KB/s, mint=37974msec, maxt=37974msec > >>>> > >>>> Disk stats (read/write): > >>>> vdb: ios=1309902/0, merge=0/0, ticks=1068768/0, in_queue=1068396, > util=99.86% > >>>> > >>>> > >>>> > >>>> qemu : iothread : glibc : iops=34516 > >>>> ------------------------------------- > >>>> > >>>> rbd_iodepth32-test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, > ioengine=libaio, iodepth=32 > >>>> fio-2.1.11 > >>>> Starting 1 process > >>>> Jobs: 1 (f=1): [r(1)] [100.0% done] [133.4MB/0KB/0KB /s] [34.2K/0/0 > iops] [eta 00m:00s] > >>>> rbd_iodepth32-test: (groupid=0, jobs=1): err= 0: pid=876: Tue Jun 9 > 18:24:01 2015 > >>>> read : io=5120.0MB, bw=137786KB/s, iops=34446, runt= 38051msec > >>>> slat (usec): min=1, max=496, avg= 3.88, stdev= 3.66 > >>>> clat (usec): min=283, max=7515, avg=923.34, stdev=300.28 > >>>> lat (usec): min=286, max=7519, avg=927.58, stdev=300.02 > >>>> clat percentiles (usec): > >>>> | 1.00th=[ 506], 5.00th=[ 564], 10.00th=[ 596], 20.00th=[ 652], > >>>> | 30.00th=[ 724], 40.00th=[ 804], 50.00th=[ 884], 60.00th=[ 964], > >>>> | 70.00th=[ 1048], 80.00th=[ 1144], 90.00th=[ 1304], 95.00th=[ 1448], > >>>> | 99.00th=[ 1896], 99.50th=[ 2096], 99.90th=[ 2480], 99.95th=[ 2640], > >>>> | 99.99th=[ 3984] > >>>> bw (KB /s): min=102680, max=171112, per=100.00%, avg=137877.78, > stdev=15521.30 > >>>> lat (usec) : 500=0.84%, 750=32.97%, 1000=30.82% > >>>> lat (msec) : 2=34.65%, 4=0.71%, 10=0.01% > >>>> cpu : usr=7.42%, sys=19.47%, ctx=52455, majf=0, minf=38 > >>>> IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, > >=64=0.0% > >>>> submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > >>>> complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, > >=64=0.0% > >>>> issued : total=r=1310720/w=0/d=0, short=r=0/w=0/d=0 > >>>> latency : target=0, window=0, percentile=100.00%, depth=32 > >>>> > >>>> Run status group 0 (all jobs): > >>>> READ: io=5120.0MB, aggrb=137785KB/s, minb=137785KB/s, > maxb=137785KB/s, mint=38051msec, maxt=38051msec > >>>> > >>>> Disk stats (read/write): > >>>> vdb: ios=1307426/0, merge=0/0, ticks=1051416/0, in_queue=1050972, > util=99.85% > >>>> > >>>> > >>>> > >>>> qemu : no iothread : glibc : iops=33395 > >>>> ----------------------------------------- > >>>> rbd_iodepth32-test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, > ioengine=libaio, iodepth=32 > >>>> fio-2.1.11 > >>>> Starting 1 process > >>>> Jobs: 1 (f=1): [r(1)] [100.0% done] [125.4MB/0KB/0KB /s] [32.9K/0/0 > iops] [eta 00m:00s] > >>>> rbd_iodepth32-test: (groupid=0, jobs=1): err= 0: pid=886: Tue Jun 9 > 18:27:18 2015 > >>>> read : io=5120.0MB, bw=133583KB/s, iops=33395, runt= 39248msec > >>>> slat (usec): min=1, max=1054, avg= 3.86, stdev= 4.29 > >>>> clat (usec): min=139, max=12635, avg=952.85, stdev=335.51 > >>>> lat (usec): min=303, max=12638, avg=957.01, stdev=335.29 > >>>> clat percentiles (usec): > >>>> | 1.00th=[ 516], 5.00th=[ 564], 10.00th=[ 596], 20.00th=[ 652], > >>>> | 30.00th=[ 724], 40.00th=[ 820], 50.00th=[ 924], 60.00th=[ 996], > >>>> | 70.00th=[ 1080], 80.00th=[ 1176], 90.00th=[ 1336], 95.00th=[ 1528], > >>>> | 99.00th=[ 2096], 99.50th=[ 2320], 99.90th=[ 2672], 99.95th=[ 2928], > >>>> | 99.99th=[ 4832] > >>>> bw (KB /s): min=98136, max=171624, per=100.00%, avg=133682.64, > stdev=19121.91 > >>>> lat (usec) : 250=0.01%, 500=0.57%, 750=32.57%, 1000=26.98% > >>>> lat (msec) : 2=38.59%, 4=1.28%, 10=0.01%, 20=0.01% > >>>> cpu : usr=9.24%, sys=15.92%, ctx=51219, majf=0, minf=38 > >>>> IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, > >=64=0.0% > >>>> submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > >>>> complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, > >=64=0.0% > >>>> issued : total=r=1310720/w=0/d=0, short=r=0/w=0/d=0 > >>>> latency : target=0, window=0, percentile=100.00%, depth=32 > >>>> > >>>> Run status group 0 (all jobs): > >>>> READ: io=5120.0MB, aggrb=133583KB/s, minb=133583KB/s, > maxb=133583KB/s, mint=39248msec, maxt=39248msec > >>>> > >>>> Disk stats (read/write): > >>>> vdb: ios=1304526/0, merge=0/0, ticks=1075020/0, in_queue=1074536, > util=99.84% > >>>> > >>>> > >>>> > >>>> qemu : iothread : jemmaloc : iops=28023 > >>>> ---------------------------------------- > >>>> rbd_iodepth32-test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, > ioengine=libaio, iodepth=32 > >>>> fio-2.1.11 > >>>> Starting 1 process > >>>> Jobs: 1 (f=1): [r(1)] [97.9% done] [155.2MB/0KB/0KB /s] [39.1K/0/0 > iops] [eta 00m:01s] > >>>> rbd_iodepth32-test: (groupid=0, jobs=1): err= 0: pid=899: Tue Jun 9 > 18:30:26 2015 > >>>> read : io=5120.0MB, bw=112094KB/s, iops=28023, runt= 46772msec > >>>> slat (usec): min=1, max=467, avg= 4.33, stdev= 4.77 > >>>> clat (usec): min=253, max=11307, avg=1135.63, stdev=346.55 > >>>> lat (usec): min=256, max=11309, avg=1140.39, stdev=346.22 > >>>> clat percentiles (usec): > >>>> | 1.00th=[ 510], 5.00th=[ 628], 10.00th=[ 700], 20.00th=[ 820], > >>>> | 30.00th=[ 924], 40.00th=[ 1032], 50.00th=[ 1128], 60.00th=[ 1224], > >>>> | 70.00th=[ 1320], 80.00th=[ 1416], 90.00th=[ 1560], 95.00th=[ 1688], > >>>> | 99.00th=[ 2096], 99.50th=[ 2224], 99.90th=[ 2544], 99.95th=[ 2832], > >>>> | 99.99th=[ 3760] > >>>> bw (KB /s): min=91792, max=174416, per=99.90%, avg=111985.27, > stdev=17381.70 > >>>> lat (usec) : 500=0.80%, 750=13.10%, 1000=23.33% > >>>> lat (msec) : 2=61.30%, 4=1.46%, 10=0.01%, 20=0.01% > >>>> cpu : usr=7.12%, sys=17.43%, ctx=54507, majf=0, minf=38 > >>>> IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, > >=64=0.0% > >>>> submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > >>>> complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, > >=64=0.0% > >>>> issued : total=r=1310720/w=0/d=0, short=r=0/w=0/d=0 > >>>> latency : target=0, window=0, percentile=100.00%, depth=32 > >>>> > >>>> Run status group 0 (all jobs): > >>>> READ: io=5120.0MB, aggrb=112094KB/s, minb=112094KB/s, > maxb=112094KB/s, mint=46772msec, maxt=46772msec > >>>> > >>>> Disk stats (read/write): > >>>> vdb: ios=1309169/0, merge=0/0, ticks=1305796/0, in_queue=1305376, > util=98.68% > >>>> > >>>> > >>>> > >>>> qemu : non-iothread : jemmaloc : iops=42226 > >>>> -------------------------------------------- > >>>> rbd_iodepth32-test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, > ioengine=libaio, iodepth=32 > >>>> fio-2.1.11 > >>>> Starting 1 process > >>>> Jobs: 1 (f=1): [r(1)] [100.0% done] [171.2MB/0KB/0KB /s] [43.9K/0/0 > iops] [eta 00m:00s] > >>>> rbd_iodepth32-test: (groupid=0, jobs=1): err= 0: pid=892: Tue Jun 9 > 18:34:11 2015 > >>>> read : io=5120.0MB, bw=177130KB/s, iops=44282, runt= 29599msec > >>>> slat (usec): min=1, max=527, avg= 3.80, stdev= 3.74 > >>>> clat (usec): min=174, max=3841, avg=717.08, stdev=237.53 > >>>> lat (usec): min=210, max=3844, avg=721.23, stdev=237.22 > >>>> clat percentiles (usec): > >>>> | 1.00th=[ 354], 5.00th=[ 422], 10.00th=[ 462], 20.00th=[ 516], > >>>> | 30.00th=[ 572], 40.00th=[ 628], 50.00th=[ 684], 60.00th=[ 740], > >>>> | 70.00th=[ 804], 80.00th=[ 884], 90.00th=[ 1004], 95.00th=[ 1128], > >>>> | 99.00th=[ 1544], 99.50th=[ 1672], 99.90th=[ 1928], 99.95th=[ 2064], > >>>> | 99.99th=[ 2608] > >>>> bw (KB /s): min=138120, max=230816, per=100.00%, avg=177192.14, > stdev=23440.79 > >>>> lat (usec) : 250=0.01%, 500=16.24%, 750=45.93%, 1000=27.46% > >>>> lat (msec) : 2=10.30%, 4=0.07% > >>>> cpu : usr=10.14%, sys=23.84%, ctx=60938, majf=0, minf=39 > >>>> IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, > >=64=0.0% > >>>> submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > >>>> complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, > >=64=0.0% > >>>> issued : total=r=1310720/w=0/d=0, short=r=0/w=0/d=0 > >>>> latency : target=0, window=0, percentile=100.00%, depth=32 > >>>> > >>>> Run status group 0 (all jobs): > >>>> READ: io=5120.0MB, aggrb=177130KB/s, minb=177130KB/s, > maxb=177130KB/s, mint=29599msec, maxt=29599msec > >>>> > >>>> Disk stats (read/write): > >>>> vdb: ios=1303992/0, merge=0/0, ticks=798008/0, in_queue=797636, > util=99.80% > >>>> > >>>> > >>>> > >>>> ----- Mail original ----- > >>>> De: "Robert LeBlanc" < rob...@leblancnet.us > > >>>> À: "aderumier" < aderum...@odiso.com > > >>>> Cc: "Mark Nelson" < mnel...@redhat.com >, "ceph-devel" < > ceph-de...@vger.kernel.org >, "pushpesh sharma" < pushpesh....@gmail.com > >, "ceph-users" < ceph-users@lists.ceph.com > > >>>> Envoyé: Mardi 9 Juin 2015 18:00:29 > >>>> Objet: Re: [ceph-users] rbd_cache, limiting read on high iops around > 40k > >>>> > >>>> -----BEGIN PGP SIGNED MESSAGE----- > >>>> Hash: SHA256 > >>>> > >>>> I also saw a similar performance increase by using alternative memory > >>>> allocators. What I found was that Ceph OSDs performed well with either > >>>> tcmalloc or jemalloc (except when RocksDB was built with jemalloc > >>>> instead of tcmalloc, I'm still working to dig into why that might be > >>>> the case). > >>>> > >>>> However, I found that tcmalloc with QEMU/KVM was very detrimental to > >>>> small I/O, but provided huge gains in I/O >=1MB. Jemalloc was much > >>>> better for QEMU/KVM in the tests that we ran. [1] > >>>> > >>>> I'm currently looking into I/O bottlenecks around the 16KB range and > >>>> I'm seeing a lot of time in thread creation and destruction, the > >>>> memory allocators are quite a bit down the list (both fio with > >>>> ioengine rbd and on the OSDs). I wonder what the difference can be. > >>>> I've tried using the async messenger but there wasn't a huge > >>>> difference. [2] > >>>> > >>>> Further down the rabbit hole.... > >>>> > >>>> [1] > https://www.mail-archive.com/ceph-users@lists.ceph.com/msg20197.html > >>>> [2] > https://www.mail-archive.com/ceph-devel@vger.kernel.org/msg23982.html > >>>> -----BEGIN PGP SIGNATURE----- > >>>> Version: Mailvelope v0.13.1 > >>>> Comment: https://www.mailvelope.com > >>>> > >>>> wsFcBAEBCAAQBQJVdw2ZCRDmVDuy+mK58QAA4MwP/1vt65cvTyyVGGSGRrE8 > >>>> unuWjafMHzl486XH+EaVrDVTXFVFOoncJ6kugSpD7yavtCpZNdhsIaTRZguU > >>>> YpfAppNAJU5biSwNv9QPI7kPP2q2+I7Z8ZkvhcVnkjIythoeNnSjV7zJrw87 > >>>> afq46GhPHqEXdjp3rOB4RRPniOMnub5oU6QRnKn3HPW8Dx9ZqTeCofRDnCY2 > >>>> S695Dt1gzt0ERUOgrUUkt0FQJdkkV6EURcUschngjtEd5727VTLp02HivVl3 > >>>> vDYWxQHPK8oS6Xe8GOW0JjulwiqlYotSlrqSU5FMU5gozbk9zMFPIUW1e+51 > >>>> 9ART8Ta2ItMhPWtAhRwwvxgy51exCy9kBc+m+ptKW5XRUXOImGcOQxszPGOO > >>>> qIIOG1vVG/GBmo/0i6tliqBFYdXmw1qFV7tFiIbisZRH7Q/1NahjYTHqHhu3 > >>>> Dv61T6WrerD+9N6S1Lrz1QYe2Fqa56BHhHSXM82NE86SVxEvUkoGegQU+c7b > >>>> 6rY1JvuJHJzva7+M2XHApYCchCs4a1Yyd1qWB7yThJD57RIyX1TOg0+siV13 > >>>> R+v6wxhQU0vBovH+5oAWmCZaPNT+F0Uvs3xWAxxaIR9r83wMj9qQeBZTKVzQ > >>>> 1aFIi15KqAwOp12yWCmrqKTeXhjwYQNd8viCQCGN7AQyPglmzfbuEHalVjz4 > >>>> oSJX > >>>> =k281 > >>>> -----END PGP SIGNATURE----- > >>>> ---------------- > >>>> Robert LeBlanc > >>>> GPG Fingerprint 79A2 9CA4 6CC4 45DD A904 C70E E654 3BB2 FA62 B9F1 > >>>> > >>>> > >>>> On Tue, Jun 9, 2015 at 6:02 AM, Alexandre DERUMIER < > aderum...@odiso.com > wrote: > >>>>>>> Frankly, I'm a little impressed that without RBD cache we can hit > 80K > >>>>>>> IOPS from 1 VM! > >>>>> > >>>>> Note that theses result are not in a vm (fio-rbd on host), so in a > vm we'll have overhead. > >>>>> (I'm planning to send results in qemu soon) > >>>>> > >>>>>>> How fast are the SSDs in those 3 OSDs? > >>>>> > >>>>> Theses results are with datas in buffer memory of osd nodes. > >>>>> > >>>>> When reading fulling on ssd (intel s3500), > >>>>> > >>>>> For 1 client, > >>>>> > >>>>> I'm around 33k iops without cache and 32k iops with cache, with 1 > osd. > >>>>> I'm around 55k iops without cache and 38k iops with cache, with 3 > osd. > >>>>> > >>>>> with multiple clients jobs, I can reach around 70kiops by osd , and > 250k iops by osd when datas are in buffer. > >>>>> > >>>>> (cpus servers/clients are 2x 10 cores 3,1ghz e5 xeon) > >>>>> > >>>>> > >>>>> > >>>>> small tip : > >>>>> I'm using tcmalloc for fio-rbd or rados bench to improve latencies > by around 20% > >>>>> > >>>>> LD_PRELOAD=/usr/lib/libtcmalloc_minimal.so.4 fio ... > >>>>> LD_PRELOAD=/usr/lib/libtcmalloc_minimal.so.4 rados bench ... > >>>>> > >>>>> as a lot of time is spent in malloc/free > >>>>> > >>>>> > >>>>> (qemu support also tcmalloc since some months , I'll bench it too > >>>>> https://lists.gnu.org/archive/html/qemu-devel/2015-03/msg05372.html > ) > >>>>> > >>>>> > >>>>> > >>>>> I'll try to send full bench results soon, from 1 to 18 ssd osd. > >>>>> > >>>>> > >>>>> > >>>>> > >>>>> ----- Mail original ----- > >>>>> De: "Mark Nelson" < mnel...@redhat.com > > >>>>> À: "aderumier" < aderum...@odiso.com >, "pushpesh sharma" < > pushpesh....@gmail.com > > >>>>> Cc: "ceph-devel" < ceph-de...@vger.kernel.org >, "ceph-users" < > ceph-users@lists.ceph.com > > >>>>> Envoyé: Mardi 9 Juin 2015 13:36:31 > >>>>> Objet: Re: [ceph-users] rbd_cache, limiting read on high iops around > 40k > >>>>> > >>>>> Hi All, > >>>>> > >>>>> In the past we've hit some performance issues with RBD cache that > we've > >>>>> fixed, but we've never really tried pushing a single VM beyond 40+K > read > >>>>> IOPS in testing (or at least I never have). I suspect there's a > couple > >>>>> of possibilities as to why it might be slower, but perhaps joshd can > >>>>> chime in as he's more familiar with what that code looks like. > >>>>> > >>>>> Frankly, I'm a little impressed that without RBD cache we can hit 80K > >>>>> IOPS from 1 VM! How fast are the SSDs in those 3 OSDs? > >>>>> > >>>>> Mark > >>>>> > >>>>>> On 06/09/2015 03:36 AM, Alexandre DERUMIER wrote: > >>>>>> It's seem that the limit is mainly going in high queue depth (+- > > 16) > >>>>>> > >>>>>> Here the result in iops with 1client- 4krandread- 3osd - with > differents queue depth size. > >>>>>> rbd_cache is almost the same than without cache with queue depth <16 > >>>>>> > >>>>>> > >>>>>> cache > >>>>>> ----- > >>>>>> qd1: 1651 > >>>>>> qd2: 3482 > >>>>>> qd4: 7958 > >>>>>> qd8: 17912 > >>>>>> qd16: 36020 > >>>>>> qd32: 42765 > >>>>>> qd64: 46169 > >>>>>> > >>>>>> no cache > >>>>>> -------- > >>>>>> qd1: 1748 > >>>>>> qd2: 3570 > >>>>>> qd4: 8356 > >>>>>> qd8: 17732 > >>>>>> qd16: 41396 > >>>>>> qd32: 78633 > >>>>>> qd64: 79063 > >>>>>> qd128: 79550 > >>>>>> > >>>>>> > >>>>>> ----- Mail original ----- > >>>>>> De: "aderumier" < aderum...@odiso.com > > >>>>>> À: "pushpesh sharma" < pushpesh....@gmail.com > > >>>>>> Cc: "ceph-devel" < ceph-de...@vger.kernel.org >, "ceph-users" < > ceph-users@lists.ceph.com > > >>>>>> Envoyé: Mardi 9 Juin 2015 09:28:21 > >>>>>> Objet: Re: [ceph-users] rbd_cache, limiting read on high iops > around 40k > >>>>>> > >>>>>> Hi, > >>>>>> > >>>>>>>> We tried adding more RBDs to single VM, but no luck. > >>>>>> > >>>>>> If you want to scale with more disks in a single qemu vm, you need > to use iothread feature from qemu and assign 1 iothread by disk (works with > virtio-blk). > >>>>>> It's working for me, I can scale with adding more disks. > >>>>>> > >>>>>> > >>>>>> My bench here are done with fio-rbd on host. > >>>>>> I can scale up to 400k iops with 10clients-rbd_cache=off on a > single host and around 250kiops 10clients-rbdcache=on. > >>>>>> > >>>>>> > >>>>>> I just wonder why I don't have performance decrease around 30k iops > with 1osd. > >>>>>> > >>>>>> I'm going to see if this tracker > >>>>>> http://tracker.ceph.com/issues/11056 > >>>>>> > >>>>>> could be the cause. > >>>>>> > >>>>>> (My master build was done some week ago) > >>>>>> > >>>>>> > >>>>>> > >>>>>> ----- Mail original ----- > >>>>>> De: "pushpesh sharma" < pushpesh....@gmail.com > > >>>>>> À: "aderumier" < aderum...@odiso.com > > >>>>>> Cc: "ceph-devel" < ceph-de...@vger.kernel.org >, "ceph-users" < > ceph-users@lists.ceph.com > > >>>>>> Envoyé: Mardi 9 Juin 2015 09:21:04 > >>>>>> Objet: Re: rbd_cache, limiting read on high iops around 40k > >>>>>> > >>>>>> Hi Alexandre, > >>>>>> > >>>>>> We have also seen something very similar on Hammer(0.94-1). We were > doing some benchmarking for VMs hosted on hypervisor (QEMU-KVM, > openstack-juno). Each Ubuntu-VM has a RBD as root disk, and 1 RBD as > additional storage. For some strange reason it was not able to scale 4K- RR > iops on each VM beyond 35-40k. We tried adding more RBDs to single VM, but > no luck. However increasing number of VMs to 4 on a single hypervisor did > scale to some extent. After this there was no much benefit we got from > adding more VMs. > >>>>>> > >>>>>> Here is the trend we have seen, x-axis is number of hypervisor, > each hypervisor has 4 VM, each VM has 1 RBD:- > >>>>>> > >>>>>> > >>>>>> > >>>>>> > >>>>>> VDbench is used as benchmarking tool. We were not saturating > network and CPUs at OSD nodes. We were not able to saturate CPUs at > hypervisors, and that is where we were suspecting of some throttling > effect. However we haven't setted any such limits from nova or kvm end. We > tried some CPU pinning and other KVM related tuning as well, but no luck. > >>>>>> > >>>>>> We tried the same experiment on a bare metal. It was 4K RR IOPs > were scaling from 40K(1 RBD) to 180K(4 RBDs). But after that rather than > scaling beyond that point the numbers were actually degrading. (Single pipe > more congestion effect) > >>>>>> > >>>>>> We never suspected that rbd cache enable could be detrimental to > performance. It would nice to route cause the problem if that is the case. > >>>>>> > >>>>>> On Tue, Jun 9, 2015 at 11:21 AM, Alexandre DERUMIER < > aderum...@odiso.com > wrote: > >>>>>> > >>>>>> > >>>>>> Hi, > >>>>>> > >>>>>> I'm doing benchmark (ceph master branch), with randread 4k > qdepth=32, > >>>>>> and rbd_cache=true seem to limit the iops around 40k > >>>>>> > >>>>>> > >>>>>> no cache > >>>>>> -------- > >>>>>> 1 client - rbd_cache=false - 1osd : 38300 iops > >>>>>> 1 client - rbd_cache=false - 2osd : 69073 iops > >>>>>> 1 client - rbd_cache=false - 3osd : 78292 iops > >>>>>> > >>>>>> > >>>>>> cache > >>>>>> ----- > >>>>>> 1 client - rbd_cache=true - 1osd : 38100 iops > >>>>>> 1 client - rbd_cache=true - 2osd : 42457 iops > >>>>>> 1 client - rbd_cache=true - 3osd : 45823 iops > >>>>>> > >>>>>> > >>>>>> > >>>>>> Is it expected ? > >>>>>> > >>>>>> > >>>>>> > >>>>>> fio result rbd_cache=false 3 osd > >>>>>> -------------------------------- > >>>>>> rbd_iodepth32-test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, > ioengine=rbd, iodepth=32 > >>>>>> fio-2.1.11 > >>>>>> Starting 1 process > >>>>>> rbd engine: RBD version: 0.1.9 > >>>>>> Jobs: 1 (f=1): [r(1)] [100.0% done] [307.5MB/0KB/0KB /s] [78.8K/0/0 > iops] [eta 00m:00s] > >>>>>> rbd_iodepth32-test: (groupid=0, jobs=1): err= 0: pid=113548: Tue > Jun 9 07:48:42 2015 > >>>>>> read : io=10000MB, bw=313169KB/s, iops=78292, runt= 32698msec > >>>>>> slat (usec): min=5, max=530, avg=11.77, stdev= 6.77 > >>>>>> clat (usec): min=70, max=2240, avg=336.08, stdev=94.82 > >>>>>> lat (usec): min=101, max=2247, avg=347.84, stdev=95.49 > >>>>>> clat percentiles (usec): > >>>>>> | 1.00th=[ 173], 5.00th=[ 209], 10.00th=[ 231], 20.00th=[ 262], > >>>>>> | 30.00th=[ 282], 40.00th=[ 302], 50.00th=[ 322], 60.00th=[ 346], > >>>>>> | 70.00th=[ 370], 80.00th=[ 402], 90.00th=[ 454], 95.00th=[ 506], > >>>>>> | 99.00th=[ 628], 99.50th=[ 692], 99.90th=[ 860], 99.95th=[ 948], > >>>>>> | 99.99th=[ 1176] > >>>>>> bw (KB /s): min=238856, max=360448, per=100.00%, avg=313402.34, > stdev=25196.21 > >>>>>> lat (usec) : 100=0.01%, 250=15.94%, 500=78.60%, 750=5.19%, > 1000=0.23% > >>>>>> lat (msec) : 2=0.03%, 4=0.01% > >>>>>> cpu : usr=74.48%, sys=13.25%, ctx=703225, majf=0, minf=12452 > >>>>>> IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.8%, 16=87.0%, 32=12.1%, > >=64=0.0% > >>>>>> submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > >>>>>> complete : 0=0.0%, 4=91.6%, 8=3.4%, 16=4.5%, 32=0.4%, 64=0.0%, > >=64=0.0% > >>>>>> issued : total=r=2560000/w=0/d=0, short=r=0/w=0/d=0 > >>>>>> latency : target=0, window=0, percentile=100.00%, depth=32 > >>>>>> > >>>>>> Run status group 0 (all jobs): > >>>>>> READ: io=10000MB, aggrb=313169KB/s, minb=313169KB/s, > maxb=313169KB/s, mint=32698msec, maxt=32698msec > >>>>>> > >>>>>> Disk stats (read/write): > >>>>>> dm-0: ios=0/45, merge=0/0, ticks=0/0, in_queue=0, util=0.00%, > aggrios=0/24, aggrmerge=0/21, aggrticks=0/0, aggrin_queue=0, aggrutil=0.00% > >>>>>> sda: ios=0/24, merge=0/21, ticks=0/0, in_queue=0, util=0.00% > >>>>>> > >>>>>> > >>>>>> > >>>>>> > >>>>>> fio result rbd_cache=true 3osd > >>>>>> ------------------------------ > >>>>>> > >>>>>> rbd_iodepth32-test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, > ioengine=rbd, iodepth=32 > >>>>>> fio-2.1.11 > >>>>>> Starting 1 process > >>>>>> rbd engine: RBD version: 0.1.9 > >>>>>> Jobs: 1 (f=1): [r(1)] [100.0% done] [171.6MB/0KB/0KB /s] [43.1K/0/0 > iops] [eta 00m:00s] > >>>>>> rbd_iodepth32-test: (groupid=0, jobs=1): err= 0: pid=113389: Tue > Jun 9 07:47:30 2015 > >>>>>> read : io=10000MB, bw=183296KB/s, iops=45823, runt= 55866msec > >>>>>> slat (usec): min=7, max=805, avg=21.26, stdev=15.84 > >>>>>> clat (usec): min=101, max=4602, avg=478.55, stdev=143.73 > >>>>>> lat (usec): min=123, max=4669, avg=499.80, stdev=146.03 > >>>>>> clat percentiles (usec): > >>>>>> | 1.00th=[ 227], 5.00th=[ 274], 10.00th=[ 306], 20.00th=[ 350], > >>>>>> | 30.00th=[ 390], 40.00th=[ 430], 50.00th=[ 470], 60.00th=[ 506], > >>>>>> | 70.00th=[ 548], 80.00th=[ 596], 90.00th=[ 660], 95.00th=[ 724], > >>>>>> | 99.00th=[ 844], 99.50th=[ 908], 99.90th=[ 1112], 99.95th=[ 1288], > >>>>>> | 99.99th=[ 2192] > >>>>>> bw (KB /s): min=115280, max=204416, per=100.00%, avg=183315.10, > stdev=15079.93 > >>>>>> lat (usec) : 250=2.42%, 500=55.61%, 750=38.48%, 1000=3.28% > >>>>>> lat (msec) : 2=0.19%, 4=0.01%, 10=0.01% > >>>>>> cpu : usr=60.27%, sys=12.01%, ctx=2995393, majf=0, minf=14100 > >>>>>> IO depths : 1=0.1%, 2=0.1%, 4=0.2%, 8=13.5%, 16=81.0%, 32=5.3%, > >=64=0.0% > >>>>>> submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > >>>>>> complete : 0=0.0%, 4=95.0%, 8=0.1%, 16=1.0%, 32=4.0%, 64=0.0%, > >=64=0.0% > >>>>>> issued : total=r=2560000/w=0/d=0, short=r=0/w=0/d=0 > >>>>>> latency : target=0, window=0, percentile=100.00%, depth=32 > >>>>>> > >>>>>> Run status group 0 (all jobs): > >>>>>> READ: io=10000MB, aggrb=183295KB/s, minb=183295KB/s, > maxb=183295KB/s, mint=55866msec, maxt=55866msec > >>>>>> > >>>>>> Disk stats (read/write): > >>>>>> dm-0: ios=0/61, merge=0/0, ticks=0/8, in_queue=8, util=0.01%, > aggrios=0/29, aggrmerge=0/32, aggrticks=0/8, aggrin_queue=8, aggrutil=0.01% > >>>>>> sda: ios=0/29, merge=0/32, ticks=0/8, in_queue=8, util=0.01% > >>>>> _______________________________________________ > >>>>> ceph-users mailing list > >>>>> ceph-users@lists.ceph.com > >>>>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > >>>> _______________________________________________ > >>>> ceph-users mailing list > >>>> ceph-users@lists.ceph.com > >>>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > >>>> > >>>> > >>>> > >>>> > >>>> > >>>> > >>>> -- > >>>> С уважением, Фасихов Ирек Нургаязович > >>>> Моб.: +79229045757 > >>>> _______________________________________________ > >>>> ceph-users mailing list > >>>> ceph-users@lists.ceph.com > >>>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > >>>> > >>>> ________________________________ > >>>> > >>>> PLEASE NOTE: The information contained in this electronic mail > message is intended only for the use of the designated recipient(s) named > above. If the reader of this message is not the intended recipient, you are > hereby notified that you have received this message in error and that any > review, dissemination, distribution, or copying of this message is strictly > prohibited. If you have received this communication in error, please notify > the sender by telephone or e-mail (as shown above) immediately and destroy > any and all copies of this message in your possession (whether hard copies > or electronically stored copies). > >>> > >>> > >>> > >>> -- > >>> -Pushpesh > >> > >> > >> > >> -- > >> -Pushpesh > > > > > > > > -- > > -Pushpesh > > > > > > -- > > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > > > > > > > -- > С уважением, Фасихов Ирек Нургаязович > Моб.: +79229045757 > > > -- С уважением, Фасихов Ирек Нургаязович Моб.: +79229045757
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