Re: performance degredation every 30 seconds

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Aha.... Insightful question!
running rados bench write to the same pool, does not exhibit any problems. It consistently shows around 480M/sec throughput, every second.

So this would seem to be something to do with using rbd devices. Which we need to do.

For what it's worth, I'm using Micron 5200 Pro SSDs on all nodes.


----- Original Message -----
From: "Jason Dillaman" <jdillama@xxxxxxxxxx>
To: "Philip Brown" <pbrown@xxxxxxxxxx>
Cc: "ceph-users" <ceph-users@xxxxxxx>
Sent: Monday, December 14, 2020 8:33:09 AM
Subject: Re:  performance degredation every 30 seconds

On Mon, Dec 14, 2020 at 11:28 AM Philip Brown <pbrown@xxxxxxxxxx> wrote:
>
>
> I have a new 3 node octopus cluster, set up on SSDs.
>
> I'm running fio to benchmark the setup, with
>
> fio --filename=/dev/rbd0 --direct=1 --rw=randrw --bs=4k --ioengine=libaio --iodepth=256 --numjobs=1 --time_based --group_reporting --name=iops-test-job --runtime=120 --eta-newline=1
>
>
>
> However, I notice that, approximately every 30 seconds, performance tanks for a bit.
>
> Any ideas on why, and better yet, how to get rid of the problem?

Does the same issue appear when running a direct rados bench? What
brand are your SSDs (i.e. are they data center grade)?
_______________________________________________
ceph-users mailing list -- ceph-users@xxxxxxx
To unsubscribe send an email to ceph-users-leave@xxxxxxx



[Index of Archives]     [Information on CEPH]     [Linux Filesystem Development]     [Ceph Development]     [Ceph Large]     [Ceph Dev]     [Linux USB Development]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [xfs]


  Powered by Linux