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Re: [Qemu-block] [PATCH] qcow2: Optimize L2 table cache size based on im
Re: [Qemu-block] [PATCH] qcow2: Optimize L2 table cache size based on image and cluster sizes
Fri, 7 Oct 2016 06:58:29 -0700
On Fri, Oct 7, 2016 at 6:46 AM, Frank Myhr <address@hidden> wrote:
> On 10/07/2016 06:56 AM, Alberto Garcia wrote:
>> I would like to know what's the use case you (Frank, Ed)
>> are thinking about:
>> - Are we talking about command-line options, QMP, or both?
> Command-line options alone are sufficient for my use case, which is
> configuring and starting VMs using libvirt.
>> - Do you know the size of the disk image or you want to be able to set
>> the cache size without having access to that information? In other
>> words, what's preventing you from calculating the cache size that you
> I know the disk image size, and can set cache size in bytes.
> l2-cache-size=max would be a convenience feature, *especially if it could
> become the default*. Then I could forget thinking about whether the image is
> larger than the current 8GB fully-cached threshold, and only have to
> calculate cache size in bytes in case of very large images, multiple backing
> files, or very tight memory.
Same here, using libvirt. l2-cache-size=max would be ideal. Or if
there were a cache-coverage-size option that takes an absolute number,
libvirt could set it to the image size.
[Qemu-block] [PATCH v2] qcow2: Add cache-size=max option to optimize caches for performance, Ed Swierk, 2016/10/04
Re: [Qemu-block] [PATCH] qcow2: Optimize L2 table cache size based on image and cluster sizes, Frank Myhr, 2016/10/06