Hello,
On Mon, 22 Sep 2014 08:55:48 -0500 Mark Nelson wrote:
> On 09/22/2014 01:55 AM, Christian Balzer wrote:
> >
> > Hello,
> >
> > not really specific to Ceph, but since one of the default questions by
> > the Ceph team when people are facing performance problems seems to be
> > "Have you tri
On 09/22/2014 01:55 AM, Christian Balzer wrote:
Hello,
not really specific to Ceph, but since one of the default questions by the
Ceph team when people are facing performance problems seems to be
"Have you tried turning it off and on again?" ^o^ err,
"Are all your interrupts on one CPU?"
I'm go
users] IRQ balancing,
distribution
but another issue is the OSD processes: do you pin those as well?
and how much data do they actually handle. to checksum, the OSD
process needs all data, so that can also cause a lot of NUMA
traffic, esp if they are not pinned.
That's why all my (productio
re as issued, lots of cycles are
lost for cache coherency.
Regards,
Anand
-Original Message-
From: ceph-users [mailto:ceph-users-boun...@lists.ceph.com] On Behalf Of Stijn
De Weirdt
Sent: Monday, September 22, 2014 2:36 PM
To: ceph-users@lists.ceph.com
Subject: Re: [ceph-users
but another issue is the OSD processes: do you pin those as well? and
how much data do they actually handle. to checksum, the OSD process
needs all data, so that can also cause a lot of NUMA traffic, esp if
they are not pinned.
That's why all my (production) storage nodes have only a single 6 or
On Mon, Sep 22, 2014 at 10:21 AM, Christian Balzer wrote:
> The linux scheduler usually is quite decent in keeping processes where the
> action is, thus you see for example a clear preference of DRBD or KVM vnet
> processes to be "near" or on the CPU(s) where the IRQs are.
Since you're just menti
Hello,
On Mon, 22 Sep 2014 09:35:10 +0200 Stijn De Weirdt wrote:
> hi christian,
>
> we once were debugging some performance isssues, and IRQ balancing was
> one of the issues we looked in, but no real benefit there for us.
> all interrupts on one cpu is only an issue if the hardware itself is
hi christian,
we once were debugging some performance isssues, and IRQ balancing was
one of the issues we looked in, but no real benefit there for us.
all interrupts on one cpu is only an issue if the hardware itself is not
the bottleneck. we were running some default SAS HBA (Dell H200), and
Hello,
not really specific to Ceph, but since one of the default questions by the
Ceph team when people are facing performance problems seems to be
"Have you tried turning it off and on again?" ^o^ err,
"Are all your interrupts on one CPU?"
I'm going to wax on about this for a bit and hope for
