Anyone can share their table with other MTU values? Also interested into Switch CPU load KR, Manuel -----Mensaje original----- De: Marc Roos <M.Roos@xxxxxxxxxxxxxxxxx> Enviado el: miércoles, 27 de mayo de 2020 12:01 Para: chris.palmer <chris.palmer@xxxxxxxxx>; paul.emmerich <paul.emmerich@xxxxxxxx> CC: amudhan83 <amudhan83@xxxxxxxxx>; anthony.datri <anthony.datri@xxxxxxxxx>; ceph-users <ceph-users@xxxxxxx>; doustar <doustar@xxxxxxxxxxxx>; kdhall <kdhall@xxxxxxxxxxxxxx>; sstkadu <sstkadu@xxxxxxxxx> Asunto: Re: [External Email] Re: Ceph Nautius not working after setting MTU 9000 Interesting table. I have this on a production cluster 10gbit at a datacenter (obviously doing not that much). [@]# iperf3 -c 10.0.0.13 -P 1 -M 9000 Connecting to host 10.0.0.13, port 5201 [ 4] local 10.0.0.14 port 52788 connected to 10.0.0.13 port 5201 [ ID] Interval Transfer Bandwidth Retr Cwnd [ 4] 0.00-1.00 sec 1.14 GBytes 9.77 Gbits/sec 0 690 KBytes [ 4] 1.00-2.00 sec 1.15 GBytes 9.90 Gbits/sec 0 1.08 MBytes [ 4] 2.00-3.00 sec 1.15 GBytes 9.88 Gbits/sec 0 1.08 MBytes [ 4] 3.00-4.00 sec 1.15 GBytes 9.88 Gbits/sec 0 1.08 MBytes [ 4] 4.00-5.00 sec 1.15 GBytes 9.88 Gbits/sec 0 1.08 MBytes [ 4] 5.00-6.00 sec 1.15 GBytes 9.90 Gbits/sec 0 1.21 MBytes [ 4] 6.00-7.00 sec 1.15 GBytes 9.89 Gbits/sec 0 1.21 MBytes [ 4] 7.00-8.00 sec 1.15 GBytes 9.88 Gbits/sec 0 1.21 MBytes [ 4] 8.00-9.00 sec 1.15 GBytes 9.89 Gbits/sec 0 1.21 MBytes [ 4] 9.00-10.00 sec 1.15 GBytes 9.89 Gbits/sec 0 1.21 MBytes - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bandwidth Retr [ 4] 0.00-10.00 sec 11.5 GBytes 9.87 Gbits/sec 0 sender [ 4] 0.00-10.00 sec 11.5 GBytes 9.87 Gbits/sec receiver -----Original Message----- Subject: Re: Re: [External Email] Re: Ceph Nautius not working after setting MTU 9000 To elaborate on some aspects that have been mentioned already and add some others:: * Test using iperf3. * Don't try to use jumbos on networks where you don't have complete control over every host. This usually includes the main ceph network. It's just too much grief. You can consider using it for limited-access networks (e.g. ceph cluster network, hypervisor migration network, etc) where you know every switch & host is tuned correctly. (This works even when those nets share a vlan trunk with non-jumbo vlans - just set the max value on the trunk itself, and individual values on each vlan.) * If you are pinging make sure it doesn't fragment otherwise you will get misleading results: e.g. ping -M do -s 9000 x.x.x.x * Do not assume that 9000 is the best value. It depends on your NICs, your switch, kernel/device parameters, etc. Try different values (using iperf3). As an example the results below are using a small cheap Mikrotek 10G switch and HPE 10G NICs. It highlights how in this configuration 9000 is worse than 1500, but that 5139 is optimal yet 5140 is worst. The same pattern (obviously with different values) was apparent when multiple tests were run concurrently. Always test your own network in a controlled manner. And of course if you introduce anything different later on, test again. With enterprise-grade kit this might not be so common, but always test if you fiddle. MTU Gbps (actual data transfer values using iperf3) - one particular configuration only 9600 8.91 (max value) 9000 8.91 8000 8.91 7000 8.91 6000 8.91 5500 8.17 5200 7.71 5150 7.64 5140 7.62 5139 9.81 (optimal) 5138 9.81 5137 9.81 5135 9.81 5130 9.81 5120 9.81 5100 9.81 5000 9.81 4000 9.76 3000 9.68 2000 9.28 1500 9.37 (default) Whether any of this will make a tangible difference for ceph is moot. I just spend a little time getting the network stack correct as above, then leave it. That way I know I am probably getting some benefit, and not doing any harm. If you blindly change things you may well do harm that can manifest itself in all sorts of ways outside of Ceph. Getting some test results for this using Ceph will be easy; getting MEANINGFUL results that way will be hard. Chris On 27/05/2020 09:25, Marc Roos wrote: I would not call a ceph page, a random tuning tip. At least I hope they are not. NVMe-only with 100Gbit is not really a standard setup. I assume with such setup you have the luxury to not notice many optimizations. What I mostly read is that changing to mtu 9000 will allow you to better saturate the 10Gbit adapter, and I expect this to show on a low end busy cluster. Don't you have any test results of such a setup? -----Original Message----- Subject: Re: Re: [External Email] Re: Ceph Nautius not working after setting MTU 9000 Don't optimize stuff without benchmarking *before and after*, don't apply random tuning tipps from the Internet without benchmarking them. My experience with Jumbo frames: 3% performance. On a NVMe-only setup with 100 Gbit/s network. Paul -- Paul Emmerich Looking for help with your Ceph cluster? Contact us at https://croit.io croit GmbH Freseniusstr. 31h 81247 München www.croit.io Tel: +49 89 1896585 90 On Tue, May 26, 2020 at 7:02 PM Marc Roos <M.Roos@xxxxxxxxxxxxxxxxx> <mailto:M.Roos@xxxxxxxxxxxxxxxxx> wrote: Look what I have found!!! :) https://ceph.com/geen-categorie/ceph-loves-jumbo-frames/ -----Original Message----- From: Anthony D'Atri [mailto:anthony.datri@xxxxxxxxx] Sent: maandag 25 mei 2020 22:12 To: Marc Roos Cc: kdhall; martin.verges; sstkadu; amudhan83; ceph-users; doustar Subject: Re: Re: [External Email] Re: Ceph Nautius not working after setting MTU 9000 Quick and easy depends on your network infrastructure. Sometimes it is difficult or impossible to retrofit a live cluster without disruption. > On May 25, 2020, at 1:03 AM, Marc Roos <M.Roos@xxxxxxxxxxxxxxxxx> <mailto:M.Roos@xxxxxxxxxxxxxxxxx> wrote: > > > I am interested. I am always setting mtu to 9000. To be honest I > cannot imagine there is no optimization since you have less interrupt > requests, and you are able x times as much data. Every time there > something written about optimizing the first thing mention is changing > to the mtu 9000. Because it is quick and easy win. > > > > > -----Original Message----- > From: Dave Hall [mailto:kdhall@xxxxxxxxxxxxxx] > Sent: maandag 25 mei 2020 5:11 > To: Martin Verges; Suresh Rama > Cc: Amudhan P; Khodayar Doustar; ceph-users > Subject: Re: [External Email] Re: Ceph Nautius not > working after setting MTU 9000 > > All, > > Regarding Martin's observations about Jumbo Frames.... > > I have recently been gathering some notes from various internet > sources regarding Linux network performance, and Linux performance in > general, to be applied to a Ceph cluster I manage but also to the rest > of the Linux server farm I'm responsible for. > > In short, enabling Jumbo Frames without also tuning a number of other > kernel and NIC attributes will not provide the performance increases > we'd like to see. I have not yet had a chance to go through the rest > of the testing I'd like to do, but I can confirm (via iperf3) that > only enabling Jumbo Frames didn't make a significant difference. > > Some of the other attributes I'm referring to are incoming and > outgoing buffer sizes at the NIC, IP, and TCP levels, interrupt > coalescing, NIC offload functions that should or shouldn't be turned > on, packet queuing disciplines (tc), the best choice of TCP slow-start > algorithms, and other TCP features and attributes. > > The most off-beat item I saw was something about adding IPTABLES rules > to bypass CONNTRACK table lookups. > > In order to do anything meaningful to assess the effect of all of > these settings I'd like to figure out how to set them all via Ansible > - so more to learn before I can give opinions. > > --> If anybody has added this type of configuration to Ceph Ansible, > I'd be glad for some pointers. > > I have started to compile a document containing my notes. It's rough, > but I'd be glad to share if anybody is interested. > > -Dave > > Dave Hall > Binghamton University > >> On 5/24/2020 12:29 PM, Martin Verges wrote: >> >> Just save yourself the trouble. You won't have any real benefit from > MTU >> 9000. It has some smallish, but it is not worth the effort, problems, > and >> loss of reliability for most environments. >> Try it yourself and do some benchmarks, especially with your regular >> workload on the cluster (not the maximum peak performance), then drop > the >> MTU to default ;). >> >> Please if anyone has other real world benchmarks showing huge > differences >> in regular Ceph clusters, please feel free to post it here. >> >> -- >> Martin Verges >> Managing director >> >> Mobile: +49 174 9335695 >> E-Mail: martin.verges@xxxxxxxx >> Chat: https://t.me/MartinVerges >> >> croit GmbH, Freseniusstr. 31h, 81247 Munich >> CEO: Martin Verges - VAT-ID: DE310638492 Com. register: Amtsgericht >> Munich HRB 231263 >> >> Web: https://croit.io >> YouTube: https://goo.gl/PGE1Bx >> >> >>> Am So., 24. Mai 2020 um 15:54 Uhr schrieb Suresh Rama >> <sstkadu@xxxxxxxxx> <mailto:sstkadu@xxxxxxxxx> : >> >>> Ping with 9000 MTU won't get response as I said and it should be > 8972. Glad >>> it is working but you should know what happened to avoid this issue > later. >>> >>>> On Sun, May 24, 2020, 3:04 AM Amudhan P <amudhan83@xxxxxxxxx> <mailto:amudhan83@xxxxxxxxx> wrote: >>> >>>> No, ping with MTU size 9000 didn't work. >>>> >>>> On Sun, May 24, 2020 at 12:26 PM Khodayar Doustar > <doustar@xxxxxxxxxxxx> <mailto:doustar@xxxxxxxxxxxx> >>>> wrote: >>>> >>>>> Does your ping work or not? >>>>> >>>>> >>>>> On Sun, May 24, 2020 at 6:53 AM Amudhan P <amudhan83@xxxxxxxxx> <mailto:amudhan83@xxxxxxxxx> > wrote: >>>>> >>>>>> Yes, I have set setting on the switch side also. >>>>>> >>>>>> On Sat 23 May, 2020, 6:47 PM Khodayar Doustar, > <doustar@xxxxxxxxxxxx> <mailto:doustar@xxxxxxxxxxxx> >>>>>> wrote: >>>>>> >>>>>>> Problem should be with network. When you change MTU it should be >>>> changed >>>>>>> all over the network, any single hup on your network should >>>>>>> speak > and >>>>>>> accept 9000 MTU packets. you can check it on your hosts with >>> "ifconfig" >>>>>>> command and there is also equivalent commands for other >>>> network/security >>>>>>> devices. >>>>>>> >>>>>>> If you have just one node which it not correctly configured for > MTU >>>> 9000 >>>>>>> it wouldn't work. >>>>>>> >>>>>>> On Sat, May 23, 2020 at 2:30 PM sinan@xxxxxxxx <sinan@xxxxxxxx> <mailto:sinan@xxxxxxxx> >>> wrote: >>>>>>>> Can the servers/nodes ping eachother using large packet sizes? >>>>>>>> I >>> guess >>>>>>>> not. >>>>>>>> >>>>>>>> Sinan Polat >>>>>>>> >>>>>>>>> Op 23 mei 2020 om 14:21 heeft Amudhan P <amudhan83@xxxxxxxxx> <mailto:amudhan83@xxxxxxxxx> > het >>>>>>>> volgende geschreven: >>>>>>>>> In OSD logs "heartbeat_check: no reply from OSD" >>>>>>>>> >>>>>>>>>> On Sat, May 23, 2020 at 5:44 PM Amudhan P > <amudhan83@xxxxxxxxx> <mailto:amudhan83@xxxxxxxxx> >>>>>>>> wrote: >>>>>>>>>> Hi, >>>>>>>>>> >>>>>>>>>> I have set Network switch with MTU size 9000 and also in my >>> netplan >>>>>>>>>> configuration. >>>>>>>>>> >>>>>>>>>> What else needs to be checked? >>>>>>>>>> >>>>>>>>>> >>>>>>>>>>> On Sat, May 23, 2020 at 3:39 PM Wido den Hollander < >>> wido@xxxxxxxx >>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>>> On 5/23/20 12:02 PM, Amudhan P wrote: >>>>>>>>>>>> Hi, >>>>>>>>>>>> >>>>>>>>>>>> I am using ceph Nautilus in Ubuntu 18.04 working fine wit > MTU >>>> size >>>>>>>> 1500 >>>>>>>>>>>> (default) recently i tried to update MTU size to 9000. >>>>>>>>>>>> After setting Jumbo frame running ceph -s is timing out. >>>>>>>>>>> Ceph can run just fine with an MTU of 9000. But there is >>> probably >>>>>>>>>>> something else wrong on the network which is causing this. >>>>>>>>>>> >>>>>>>>>>> Check the Jumbo Frames settings on all the switches as well > to >>>> make >>>>>>>> sure >>>>>>>>>>> they forward all the packets. >>>>>>>>>>> >>>>>>>>>>> This is definitely not a Ceph issue. >>>>>>>>>>> >>>>>>>>>>> Wido >>>>>>>>>>> >>>>>>>>>>>> regards >>>>>>>>>>>> Amudhan P >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> ceph-users mailing list -- ceph-users@xxxxxxx To >>>>>>>>>>>> unsubscribe send an email to ceph-users-leave@xxxxxxx >>>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe >>>>>>>>>>> send an email to ceph-users-leave@xxxxxxx >>>>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe >>>>>>>>> send an email to ceph-users-leave@xxxxxxx >>>>>>>> _______________________________________________ >>>>>>>> ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe >>>>>>>> send an email to ceph-users-leave@xxxxxxx >>>>>>>> >>>> _______________________________________________ >>>> ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send >>>> an email to ceph-users-leave@xxxxxxx >>>> >>> _______________________________________________ >>> ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an >>> email to ceph-users-leave@xxxxxxx >>> >> _______________________________________________ >> ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an >> email to ceph-users-leave@xxxxxxx > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an > email to ceph-users-leave@xxxxxxx > > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an > email to ceph-users-leave@xxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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