-Original Message-
> From: ceph-users [mailto:ceph-users-boun...@lists.ceph.com] On Behalf Of
> Christian Balzer
> Sent: 04 March 2015 08:40
> To: ceph-users@lists.ceph.com
> Cc: Nick Fisk
> Subject: Re: [ceph-users] Persistent Write Back Cache
>
>
> Hello,
>
>
On 03/04/2015 05:34 AM, John Spray wrote:
On 04/03/2015 08:26, Nick Fisk wrote:
To illustrate the difference a proper write back cache can make, I put
a 1GB (512mb dirty threshold) flashcache in front of my RBD and
tweaked the flush parameters to flush dirty blocks at a large queue
depth. The
From: ceph-users [mailto:ceph-users-boun...@lists.ceph.com] On Behalf Of
John Spray
Sent: 04 March 2015 11:34
To: Nick Fisk; ceph-users@lists.ceph.com
Subject: Re: [ceph-users] Persistent Write Back Cache
On 04/03/2015 08:26, Nick Fisk wrote:
To illustrate the difference a
f you are using Qemu and RBD.
>
> Nick
>
> -Original Message-
> From: ceph-users [mailto:ceph-users-boun...@lists.ceph.com] On Behalf Of
> Christian Balzer
> Sent: 04 March 2015 08:40
> To: ceph-users@lists.ceph.com
> Cc: Nick Fisk
> Subject: Re: [ceph-users]
On 04/03/2015 08:26, Nick Fisk wrote:
To illustrate the difference a proper write back cache can make, I put
a 1GB (512mb dirty threshold) flashcache in front of my RBD and
tweaked the flush parameters to flush dirty blocks at a large queue
depth. The same fio test (128k iodepth=1) now runs a
c: Nick Fisk
Subject: Re: [ceph-users] Persistent Write Back Cache
Hello,
If I understand you correctly, you're talking about the rbd cache on the
client side.
So assume that host or the cache SSD on if fail terminally.
The client thinks its sync'ed are on the permanent storage (t
Hello,
If I understand you correctly, you're talking about the rbd cache on the
client side.
So assume that host or the cache SSD on if fail terminally.
The client thinks its sync'ed are on the permanent storage (the actual ceph
storage cluster), while they are only present locally.
So restart
Hi All,
Is there anything in the pipeline to add the ability to write the librbd
cache to ssd so that it can safely ignore sync requests? I have seen a
thread a few years back where Sage was discussing something similar, but I
can't find anything more recent discussing it.
I've been running
