[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit
From: |
Kevin Wolf |
Subject: |
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size |
Date: |
Mon, 13 Aug 2018 18:00:25 +0200 |
User-agent: |
Mutt/1.9.1 (2017-09-22) |
Am 13.08.2018 um 17:16 hat Max Reitz geschrieben:
> On 2018-08-13 08:09, Leonid Bloch wrote:
> > On August 13, 2018 4:39:35 AM EEST, Max Reitz <address@hidden> wrote:
>
> [...]
>
> >> Ideally we'd probably want a soft and a hard cache limit, but I don't
> >> know...
> >>
> >> (Like, a soft cache limit of 1 MB with a CCI of 10 min, and a hard
> >> cache
> >> limit of 32 MB with a CCI of 1 min by default. So whenever your cache
> >> uses more than 1 MB of RAM, your CCI is 1 min, and whenever it's below,
> >> your CCI is 10 min.)
> >
> > Max, thanks for your insight. Indeed some good points.
> > Considering this, I'm thinking to set the limit to 16 MB, and the CCI to 5
> > min. What do you think?
>
> I think it's good for a preliminary solution, and then later increase
> the limit with the soft and hard limits.
>
> OTOH, if we implement the soft/hard limits, it doesn't really matter
> what default you choose now...
>
> > Modern Windows installations should gain performance from being able to
> > random I/O to >8 GB chunks, and data processing tasks where each data set
> > is 8+ GB for sure do (did benchmarks). And the maximum is only ever used if
> > (a) the image is large enough and (b) it is indeed used.
> > While taking 256 GB images as the "limit" can be considered an overshoot,
> > 128 GB is quite reasonable, I think.
> >
> > Your idea with "soft" and "hard" limits is great! I'm tempted to implement
> > this. Say 4 MB with 10 min., and 16 MB with 5 min?
>
> 32 MB and 2 or 3 min? :-)
>
> If you do that, I'm fine with a plain default of 32 MB for now.
I would be happy with that.
Kevin
signature.asc
Description: PGP signature
- [Qemu-devel] [PATCH v7 5/9] qcow2: Assign the L2 cache relatively to the image size, (continued)
[Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Leonid Bloch, 2018/08/10
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Kevin Wolf, 2018/08/13
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Max Reitz, 2018/08/13
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Kevin Wolf, 2018/08/13
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Max Reitz, 2018/08/13
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Kevin Wolf, 2018/08/13
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Leonid Bloch, 2018/08/13
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Kevin Wolf, 2018/08/14
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Leonid Bloch, 2018/08/14
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Kevin Wolf, 2018/08/14
Re: [Qemu-devel] [PATCH v7 6/9] qcow2: Increase the default upper limit on the L2 cache size, Leonid Bloch, 2018/08/14