Re: [ceph-users] First Reef release candidate - v18.1.0
Hi Michal, Thank you for volunteering to help test the Reef release! On Tue, Jun 27, 2023 at 6:44 AM Michal Strnad <michal.strnad@cesnet.cz> wrote:
Hi everyone,
We read that you are looking for ceph users who would be willing to help with performance testing of a new version of Ceph called Reef. We would like to volunteer and offer our assistance :-).
Currently, we are setting up a large cluster consisting of fifty storage nodes, each with 24 rotational disks and 8 NVMe drives, some of which are designated for Bluestore and others for data purposes. Each of these machines is equipped with an AMD EPYC 7282 16-Core processor, ~314GB of memory, and a 2x25Gbps network connection. The network on each of these machines is used for both public and cluster communication, and if necessary, we can prioritize one over the other through QoS adjustments within the VLAN. However, we haven't had the need to do so thus far.
Furthermore, we have sixteen application servers for monitors, MGR, metadata servers, and radosgw gateways. Each of these application servers is equipped with an AMD EPYC 7502 32-Core processor, ~250GB of memory, and a 2x25Gbps network connection.
Both the storage and application servers are connected to two Nexus 9000 switches with connectivity reaching several 100Gbps towards the internet.
The mentioned cluster will be operational within a few weeks, with Ceph already installed and ready to undergo performance testing. Once this is ready, it will be possible to start testing the Reef version. We anticipate having approximately 2-3 weeks for testing. Are you interested in the performance results? To achieve better results, it would be beneficial to coordinate these tests in some way, so that we don't repeat what others have already tried. Could you please guide us on what specific aspects we should focus on, which parameters to test, and how to properly conduct the tests?
We are particularly interested to see the performance impact of the new RockDB version we'll be shipping with Reef. I am adding Mark to this email to provide guidance on performance tests.
After an agreement, it will be possible to arrange some form of access to the machines, for example, by meeting via video conference and fine-tuning them together. Alternatively, we can also work on it through email, IRC, Slack, or any other suitable means.
We are coordinating community efforts around such testing in #ceph-at-scale slack channel in ceph-storage.slack.com. I sent you an invite. Thanks, Neha
Kind regards, Michal Strnad
Hi everyone,
This is the first release candidate for Reef.
The Reef release comes with a new RockDB version (7.9.2) [0], which incorporates several performance improvements and features. Our internal testing doesn't show any side effects from the new version, but we are very eager to hear community feedback on it. This is the first release to have the ability to tune RockDB settings per column family [1], which allows for more granular tunings to be applied to different kinds of data stored in RocksDB. A new set of settings has been used in Reef to optimize performance for most kinds of workloads with a slight penalty in some cases, outweighed by large improvements in use cases such as RGW, in terms of compactions and write amplification. We would highly encourage community members to give these a try against their performance benchmarks and use cases. The detailed list of changes in terms of RockDB and BlueStore can be found in https://pad.ceph.com/p/reef-rc-relnotes.
If any of our community members would like to help us with performance investigations or regression testing of the Reef release candidate,
On 6/13/23 22:27, Neha Ojha wrote: please
feel free to provide feedback via email or in https://pad.ceph.com/p/reef_scale_testing. For more active discussions, please use the #ceph-at-scale slack channel in ceph-storage.slack.com.
Overall things are looking pretty good based on our testing. Please try it out and report any issues you encounter. Happy testing!
Thanks, Neha
Get the release from
* Git at git://github.com/ceph/ceph.git * Tarball at https://download.ceph.com/tarballs/ceph-18.1.0.tar.gz * Containers at https://quay.io/repository/ceph/ceph * For packages, see https://docs.ceph.com/en/latest/install/get-packages/ * Release git sha1: c2214eb5df9fa034cc571d81a32a5414d60f0405
[0] https://github.com/ceph/ceph/pull/49006 [1] https://github.com/ceph/ceph/pull/51821 _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-leave@ceph.io
Hi Michal! On 6/27/23 18:02, Neha Ojha wrote:
Hi Michal,
Thank you for volunteering to help test the Reef release!
On Tue, Jun 27, 2023 at 6:44 AM Michal Strnad <michal.strnad@cesnet.cz> wrote:
Hi everyone,
We read that you are looking for ceph users who would be willing to help with performance testing of a new version of Ceph called Reef. We would like to volunteer and offer our assistance :-).
Currently, we are setting up a large cluster consisting of fifty storage nodes, each with 24 rotational disks and 8 NVMe drives, some of which are designated for Bluestore and others for data purposes. Each of these machines is equipped with an AMD EPYC 7282 16-Core processor, ~314GB of memory, and a 2x25Gbps network connection. The network on each of these machines is used for both public and cluster communication, and if necessary, we can prioritize one over the other through QoS adjustments within the VLAN. However, we haven't had the need to do so thus far.
Furthermore, we have sixteen application servers for monitors, MGR, metadata servers, and radosgw gateways. Each of these application servers is equipped with an AMD EPYC 7502 32-Core processor, ~250GB of memory, and a 2x25Gbps network connection.
Both the storage and application servers are connected to two Nexus 9000 switches with connectivity reaching several 100Gbps towards the internet.
The mentioned cluster will be operational within a few weeks, with Ceph already installed and ready to undergo performance testing. Once this is ready, it will be possible to start testing the Reef version. We anticipate having approximately 2-3 weeks for testing. Are you interested in the performance results? To achieve better results, it would be beneficial to coordinate these tests in some way, so that we don't repeat what others have already tried. Could you please guide us on what specific aspects we should focus on, which parameters to test, and how to properly conduct the tests?
We are particularly interested to see the performance impact of the new RockDB version we'll be shipping with Reef. I am adding Mark to this email to provide guidance on performance tests.
As Neha mentioned, we both did a fairly major rocksdb upgrade and also changed Ceph's default bluestore RocksDB tunings after many years. We *think* this is generally going to be an improvement, but there are some trade offs. We expect lower write latency, higher write IOPS, and reduced CPU consumption in the kv sync thread (this is a bigger deal on all-flash setups), but there's a chance that we might also see higher write-amplification on the DB device in some scenarios. In the testing I did I saw lower write amp in some tests and higher write amp in others. Paul Cuzner also ran tests over at IBM and saw higher CPU usage during reads in some tests, though I think in the most recent version of the changes those improved and he also saw the write latency improvement. His tests were primarily focused on low-medium load testing. Initially I was doing max load testing but after seeing his results also ran some low-load tests. I suspect that with HDD+Flash setups none of this is going to actually matter that much as the rotational latency of the HDDs is likely to be the dominating effect. It would be nice to verify that though. Given that this is a new cluster that you guys are setting up, we won't have any kind of historical data about existing RocksDB behavior to compare with. We can still look at the general behavior of RocksDB though and see if there's anything obviously wrong with it. I don't think we'll necessarily need cluster access unless something really interesting pops up, but perhaps Neha and Paul have something they want to look at. As far as workloads go, I'd say if you guys have any real workloads you intend to do (veaam, scientific apps, etc) that might actually be the most worthwhile. We do a lot of synthetic testing internally. Real workloads on real clusters are harder for us to do ourselves. Heavy write workloads (especially smaller writes or smaller objects) would probably be the most worthwhile for this round given the changes we're interested in looking at. Mark
After an agreement, it will be possible to arrange some form of access to the machines, for example, by meeting via video conference and fine-tuning them together. Alternatively, we can also work on it through email, IRC, Slack, or any other suitable means.
We are coordinating community efforts around such testing in #ceph-at-scale slack channel in ceph-storage.slack.com <http://ceph-storage.slack.com>. I sent you an invite.
Thanks, Neha
Kind regards, Michal Strnad
On 6/13/23 22:27, Neha Ojha wrote: > Hi everyone, > > This is the first release candidate for Reef. > > The Reef release comes with a new RockDB version (7.9.2) [0], which > incorporates several performance improvements and features. Our internal > testing doesn't show any side effects from the new version, but we are very > eager to hear community feedback on it. This is the first release to have > the ability to tune RockDB settings per column family [1], which allows for > more granular tunings to be applied to different kinds of data stored in > RocksDB. A new set of settings has been used in Reef to optimize > performance for most kinds of workloads with a slight penalty in some > cases, outweighed by large improvements in use cases such as RGW, in terms > of compactions and write amplification. We would highly encourage community > members to give these a try against their performance benchmarks and use > cases. The detailed list of changes in terms of RockDB and BlueStore can be > found in https://pad.ceph.com/p/reef-rc-relnotes. > > If any of our community members would like to help us with performance > investigations or regression testing of the Reef release candidate, please > feel free to provide feedback via email or in > https://pad.ceph.com/p/reef_scale_testing. For more active discussions, > please use the #ceph-at-scale slack channel in ceph-storage.slack.com <http://ceph-storage.slack.com>. > > Overall things are looking pretty good based on our testing. Please try it > out and report any issues you encounter. Happy testing! > > Thanks, > Neha > > Get the release from > > * Git at git://github.com/ceph/ceph.git <http://github.com/ceph/ceph.git> > * Tarball at https://download.ceph.com/tarballs/ceph-18.1.0.tar.gz > * Containers at https://quay.io/repository/ceph/ceph > * For packages, see https://docs.ceph.com/en/latest/install/get-packages/ > * Release git sha1: c2214eb5df9fa034cc571d81a32a5414d60f0405 > > [0] https://github.com/ceph/ceph/pull/49006 > [1] https://github.com/ceph/ceph/pull/51821 > _______________________________________________ > ceph-users mailing list -- ceph-users@ceph.io > To unsubscribe send an email to ceph-users-leave@ceph.io
-- Best Regards, Mark Nelson Head of R&D (USA) Clyso GmbH p: +49 89 21552391 12 a: Loristraße 8 | 80335 München | Germany w: https://clyso.com | e: mark.nelson@clyso.com We are hiring: https://www.clyso.com/jobs/
participants (2)
-
Mark Nelson
-
Neha Ojha