w32handle: double the available slots

[DragonSA]

Mono crashes if the system has more than ~128G of RAM. Doubling the
number of slots fixes the SIGSEGV error on FreeBSD.

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[luhenry]

@DragonRsa thanks for the PR! Could you please provide more context with for example the SIGSEGV you are seeing?

[DragonSA]

Please see PR 200937 on FreeBSD's bug tracker for the full details.

In summary: the normal SIGSEGV warning message is encountered ("while executing native code") when running mono-lite on a system with high memory, caused by the code running out of slots.

[luhenry]

What your change implies is that you are creating more than 4 millions handles (file, console, pipe, mutex, semaphore, event, socket, etc.). Is that expected?

[DragonSA]

If I understand the code correctly, we are changing the handles from:

• 4 million handles (SLOT_MAX(1024 * 16) * HANDLE_PER_SLOT(256)), to
• 8 million handles (SLOT_MAX(1024 * 32) * HANDLE_PER_SLOT(256))

Yes, that is expected.

[kumpera]

LGTM

The proper fix is to remove this arbitrary limit as I bet we'll run into it on machines with 1TB of ram.

[luhenry]

build