[PATCH 2/4] ntdll: Provide more accurate virtual memory counters.

[Matteo Bruni]

2017-06-06 17:35 GMT+02:00 Akihiro Sagawa <sagawa.aki at gmail.com>:
> On Mon, 5 Jun 2017 19:41:06 +0200, Matteo Bruni wrote:
>> 2017-06-05 16:15 GMT+02:00 Akihiro Sagawa <sagawa.aki at gmail.com>:
>> > On Sun, 4 Jun 2017 22:51:10 -0600, Alex Henrie wrote:
>> >> Out of curiosity, is there a particular application that depends on
>> >> this behavior? It could be argued that reporting the value from the
>> >> native operating system is better because it tells what's really
>> >> happening in the process.
>> >>
>> >> -Alex
>> >
>> > Good question. I'm trying to fix Sorcery Jokers (trial) issue, bug 43119.
>> > The application repeatedly trys to allocate virtual memory as much as
>> > possible, and measures available memory size by GlobalMemoryStatusEx().
>> >
>> > This patch is better than nothing. The application stops memory
>> > allocation about 384MB (0x17ffffff) free. After the allocation, it
>> > succeeds to load libGL.so. However, it shows driver pointer missing
>> > error when loading DRI driver, radeonsi_dri.so. I'm still in trouble
>> > with this point.
>> >
>> > By the way, I have another idea about this issue. That is reserving
>> > virtual memory area when loading wined3d.dll and release it just before
>> > loading OpenGL libraries. Being hackish idea, I chose the forementioned
>> > method in the beginning.
>>
>> As far as hacks go, does adding some arbitrary "reserved" amount to
>> pvmi.VirtualSize make any difference?
>
> Thanks comments. Could you explain why adding "reserved" amount to
> pvmi.VirtualSize helps the issue?
> From my viewpoint, if we increase pvmi.VirtualSize, available virtual memory,
> i.e. MEMORYSTATUSEX.ullAvailVirtual, will decline. And, VM allocation
> limit doesn't change.

As I understood your previous email, it sounded like the application
allocates memory until the free memory amount gets to some particular
value. By "faking" a lower free memory amount the application might
stop allocating earlier and leave enough addressing space for native
libraries.

Does it make sense? Did I misunderstand something?