[PATCH 4/4] wined3d: Allow up to 512 MB of persistently mapped memory on 32-bit architectures.

[Matteo Bruni]

On Mon, Jan 31, 2022 at 4:05 AM Zebediah Figura <zfigura at codeweavers.com> wrote:
>
> Signed-off-by: Zebediah Figura <zfigura at codeweavers.com>
> ---
> The number comes from patches by Matteo Bruni. I haven't tested it with real
> applications, though, and I don't make claims as to its appropriateness.

Good strategy to pull me in like this :D

FWIW that's the number I ended up with after running a number of games
with my patches and raising the limits whenever we kept blocking on
maps.

The commit message from the last patch in my branch touching the limit is:

With these new values Gaz Guzzler Combat Carnage is happy (on the
i7-870 + Nvidia GTX 970 box). The game needs the LAA flag set to avoid
VM exhaustion issues on the GL driver side even without these changes.

That was with a whole lot of other changes (some of them hacky) to
avoid various performance bottlenecks. OTOH that system has a slow CPU
compared to the GPU and that was with GL, it's certainly possible that
we would use as much memory on a newer setup even without the
additional hacks.

If you feel that 512MB is too much (it's 1/8 of the whole address
space after all...) we could start smaller and possibly raise the
threshold afterwards.