-Original Message-
From: Nikola Ciprich [mailto:nikola.cipr...@linuxbox.cz]
Sent: Sunday, May 10, 2015 10:33 PM
To: Somnath Roy
Cc: ceph-users; n...@linuxbox.cz
Subject: Re: [ceph-users] very different performance on two volumes in
the same pool #2
On Mon, May 11, 2015 at 05:20:25AM
: Nikola Ciprich [mailto:nikola.cipr...@linuxbox.cz]
Sent: Sunday, May 10, 2015 10:33 PM
To: Somnath Roy
Cc: ceph-users; n...@linuxbox.cz
Subject: Re: [ceph-users] very different performance on two volumes in the
same pool #2
On Mon, May 11, 2015 at 05:20:25AM +, Somnath Roy wrote:
Two
/ 1,15 / 2, 10 ?).
Thanks Regards
Somnath
-Original Message-
From: Nikola Ciprich [mailto:nikola.cipr...@linuxbox.cz]
Sent: Sunday, May 10, 2015 10:33 PM
To: Somnath Roy
Cc: ceph-users; n...@linuxbox.cz
Subject: Re: [ceph-users] very different performance on two volumes in the same
pool
Thanks Regards
Somnath
-Original Message-
From: Nikola Ciprich [mailto:nikola.cipr...@linuxbox.cz]
Sent: Sunday, May 10, 2015 10:33 PM
To: Somnath Roy
Cc: ceph-users; n...@linuxbox.cz
Subject: Re: [ceph-users] very different performance on two volumes in
the same pool #2
Hi,
I'm currently doing benchmark too, and I don't see this behavior
I get very nice performance of up to 200k IOPS. However once the volume is
written to (ie when I map it using rbd map and dd whole volume with some
random data),
and repeat the benchmark, random performance drops to ~23k IOPS.
Two things..
1. You should always use SSD drives for benchmarking after preconditioning it.
2. After creating and mapping rbd lun, you need to write data first to read it
afterword otherwise fio output will be misleading. In fact, I think you will
see IO is not even hitting cluster (check with
On Mon, May 11, 2015 at 05:20:25AM +, Somnath Roy wrote:
Two things..
1. You should always use SSD drives for benchmarking after preconditioning it.
well, I don't really understand... ?
2. After creating and mapping rbd lun, you need to write data first to read
it afterword
