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References: <20180724121753.5753-1-lbloch@janustech.com>
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From: Eric Blake <eblake@redhat.com>
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Date: Tue, 24 Jul 2018 10:22:27 -0500
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Subject: Re: [Qemu-devel] [PATCH 2/4 for-3.0] docs: Fix an inaccuracy due to
 recent changes
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To: Leonid Bloch <lbloch@janustech.com>, qemu-devel@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>, qemu-block@nongnu.org, Max Reitz <mreitz@redhat.com>

On 07/24/2018 07:17 AM, Leonid Bloch wrote:
> Signed-off-by: Leonid Bloch <lbloch@janustech.com>
> ---
>   docs/qcow2-cache.txt | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)

Updating the subject line, since this doc fix is appropriate for 3.0, if 
it is correct.

> 
> diff --git a/docs/qcow2-cache.txt b/docs/qcow2-cache.txt
> index 8a09a5cc5f..a0a1267482 100644
> --- a/docs/qcow2-cache.txt
> +++ b/docs/qcow2-cache.txt
> @@ -97,9 +97,9 @@ need:
>      l2_cache_size = disk_size_GB * 131072
>      refcount_cache_size = disk_size_GB * 32768
>   
> -QEMU has a default L2 cache of 1MB (1048576 bytes) and a refcount
> -cache of 256KB (262144 bytes), so using the formulas we've just seen
> -we have
> +QEMU has a default L2 cache of 1MB (1048576 bytes) or 8 clusters (whichever
> +is larger) and a refcount cache of 256KB (262144 bytes), so using the
> +formulas we've just seen we have (assuming the L2 cache is 1MB):
>   
>      1048576 / 131072 = 8 GB of virtual disk covered by that cache
>       262144 /  32768 = 8 GB
> 

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org