Re: [Qemu-devel] [PATCH v6 5/6] iotests: Add new test 214 for max compressed cluster offset

[Alberto Garcia]

On Thu 26 Apr 2018 04:51:28 AM CEST, Eric Blake wrote:
> If you have a capable file system (tmpfs is good, ext4 not so much;
> run ./check with TEST_DIR pointing to a good location so as not
> to skip the test), it's actually possible to create a qcow2 file
> that expands to a sparse 512T image with just over 38M of content.
> The test is not the world's fastest (qemu crawling through 256M
> bits of refcount table to find the next cluster to allocate takes
> several seconds, as does qemu-img check reporting millions of
> leaked clusters); but it DOES catch the problem that the previous
> patch just fixed where writing a compressed cluster to a full
> image ended up overwriting the wrong cluster.
>
> Suggested-by: Max Reitz <address@hidden>
> Signed-off-by: Eric Blake <address@hidden>

Nice test :-)

Reviewed-by: Alberto Garcia <address@hidden>

Berto