Re: [ceph-users] Experience with 5k RPM/archive HDDs

Maxime I forgot to mention a couple more things that you can try when using SMR HDD. You could try to use ext4 with the “lazy” initialization. Another option is specifying the “lazytime” ext4 mount option. Depending on your workload, you could possibly see some big improvements. Rick > On Feb

Re: [ceph-users] Experience with 5k RPM/archive HDDs

Hi, again, as I said, in normal operation everything is fine with SMR. They perform well in particular for large sequential writes because of the on platter cache (20 GB I think). All tests we have done were with good SSDs for OSD cache. Things blow up during backfill / recovery because the

Re: [ceph-users] Experience with 5k RPM/archive HDDs

> Op 18 februari 2017 om 17:03 schreef rick stehno : > > > I work for Seagate and have done over a hundred of tests using SMR 8TB disks > in a cluster. It all depends on what your access is if SMR hdd would be the > best choice. Remember SMR hdd don't perform well doing random

Re: [ceph-users] Experience with 5k RPM/archive HDDs

Hi Rick, If you have some numbers and info on the setup that would be greatly appreciated. I noticed Wildo's blog post about SMR drives: https://blog.widodh.nl/2017/02/do-not-use-smr-disks-with-ceph/ so I guess he ran into some problems? Cheers, Maxime On Feb 18, 2017 23:04, rick stehno

Re: [ceph-users] Experience with 5k RPM/archive HDDs

I work for Seagate and have done over a hundred of tests using SMR 8TB disks in a cluster. It all depends on what your access is if SMR hdd would be the best choice. Remember SMR hdd don't perform well doing random writes, but are excellent for reads and sequential writes. I have many tests

Re: [ceph-users] Experience with 5k RPM/archive HDDs

Hi, don't go there, we tried this with SMR drives, which will slow down to somewhere around 2-3 IOPS during backfilling/recovery and that renders the cluster useless for client IO. Things might change in the future, but for now, I would strongly recommend against SMR. Go for normal SATA

Re: [ceph-users] Experience with 5k RPM/archive HDDs

On 2/3/17, 3:23 AM, "ceph-users on behalf of Wido den Hollander" wrote: > >> Op 3 februari 2017 om 11:03 schreef Maxime Guyot >>: >> >> >> Hi, >> >> Interesting feedback! >> >> > In my opinion the SMR can

Re: [ceph-users] Experience with 5k RPM/archive HDDs

> Op 3 februari 2017 om 11:03 schreef Maxime Guyot : > > > Hi, > > Interesting feedback! > > > In my opinion the SMR can be used exclusively for the RGW. > > Unless it's something like a backup/archive cluster or pool with little to > none concurrent R/W access,

Re: [ceph-users] Experience with 5k RPM/archive HDDs

Hi, Interesting feedback! > In my opinion the SMR can be used exclusively for the RGW. > Unless it's something like a backup/archive cluster or pool with little to > none concurrent R/W access, you're likely to run out of IOPS (again) long > before filling these monsters up. That’s

Re: [ceph-users] Experience with 5k RPM/archive HDDs

> Op 3 februari 2017 om 8:39 schreef Christian Balzer : > > > > Hello, > > On Fri, 3 Feb 2017 10:30:28 +0300 Irek Fasikhov wrote: > > > Hi, Maxime. > > > > Linux SMR is only starting with version 4.9 kernel. > > > What Irek said. > > Also, SMR in general is probably a bad

Re: [ceph-users] Experience with 5k RPM/archive HDDs

Hi, Maxime. Linux SMR is only starting with version 4.9 kernel. С уважением, Фасихов Ирек Нургаязович Моб.: +79229045757 2017-02-03 10:26 GMT+03:00 Maxime Guyot : > Hi everyone, > > > > I’m wondering if anyone in the ML is running a cluster with archive type > HDDs,

[ceph-users] Experience with 5k RPM/archive HDDs

Hi everyone, I’m wondering if anyone in the ML is running a cluster with archive type HDDs, like the HGST Ultrastar Archive (10TB@7.2k RPM) or the Seagate Enterprise Archive (8TB@5.9k RPM)? As far as I read they both fall in the enterprise class HDDs so *might* be suitable for a low