[PATCH 3/4] d3d11/tests: Don't run the 32-bit tests multithreaded.

[Henri Verbeet]

On Thu, 3 Feb 2022 at 20:17, Zebediah Figura <zfigura at codeweavers.com> wrote:
> -    if (!use_mt)
> +    /* Running the tests multithreaded on 32-bit maps too much memory in Wine,
> +     * even with only 2 threads. */

That didn't seem quite right, so I looked a bit more into this. It
seems the issue is slightly more subtle; when maps start failing with
GL_OUT_OF_MEMORY, the total number of chunks mapped across devices is
typically either 0 or 1. On the other hand, the total number of
allocated chunks tends to be fairly high (about 24, which would amount
to about 1.5GiB). It seems the radeonsi driver doesn't actually
(ever?) unmap buffers when we request that. That's probably reasonable
enough for 64-bit applications, but less so for 32-bit applications.
This doesn't happen on my Intel SKL system. A contributing factor is
probably that because there's currently no slab allocator, we allocate
blocks of WINED3D_ALLOCATOR_MIN_BLOCK_SIZE size for small constant
buffers, which is going to inflate VRAM usage somewhat.

That leaves the question of what to do about it, of course. I could
live with this series, although it seems a rather unsatisfying
solution. We probably want to adjust the comment a little though, and
I think we only want to do this on Wine, not on Windows (where running
the tests in parallel always helped a bit more than on Wine anyway).