testhost.x86 is not large address aware

[sharwell]

Currently testhost.x86 is compiled with platform set to x86:

https://github.com/Microsoft/vstest/blob/53c0a341b07c1f224a31b2378e696f535a1f6080/src/testhost.x86/testhost.x86.csproj#L12

This compilation setting causes the application to omit the large address aware setting, which causes problems on larger multi-core machines (I'm observing frequent OOM errors on 2990WX).

The correct setting for an x86 build which is large address aware is a combination of the AnyCPU platform and the Prefer32Bit setting. See microsoft/perfview@1582d04 for an example of this configuration.

[AbhitejJohn]

@sharwell : Just trying to understand the affect of moving to LAA, how would this affect low config systems?

[ivonin]

From what I read, setting the performance hit from setting the /LAA flag exists although it's not too big.

Can't find anything more thourough than this StackOverflow post at the moment. @sharwell what's your take on this?

[sharwell]

I've never heard of there being a difference. I can't benchmark the difference in a meaninful way because the current release just crashes on anything of interest to performance.