Re: [PATCH v2 6/6] iotests: Test committing to short backing file

[Kevin Wolf]

Am 21.11.2019 um 11:30 hat Vladimir Sementsov-Ogievskiy geschrieben:
> 21.11.2019 13:28, Vladimir Sementsov-Ogievskiy wrote:
> > 20.11.2019 21:45, Kevin Wolf wrote:
> >> Signed-off-by: Kevin Wolf<address@hidden>
> > 
> > Hmm, allocating 7G will break tests on small disks, for example,
> > on my 2G tmpfs.
> > 
> > So, we probably should
> > detect "+qemu-img: Failed to resize underlying file: Could not write zeros 
> > for preallocation: No space left on device"
> > errors and skip test. (better skip testcases, but it's not possible for 
> > text-comparing tests :(
> 
> Or could you just use smaller disks for resize? What is the purpose of such a 
> big size?

I want to exceed a 32 bit byte count for the write_zeroes operation so
that it would break if patch 1 were missing. I guess I could reduce it
to a little over 4 GB, but not less.

Hm, though that is only for preallocation=off, which shouldn't actually
allocate the space anyway. I could use smaller sizes for falloc and
full, even though I'm not sure if we're still testing these modes with
sizes larger than INT_MAX anywhere.

Kevin