Re: help with huge memory consumption??

Rainer Weikusat <rainer.weikusat@xxxxxxxxx> wrote in part:
The original article talked about stacks allocated for thread
within a process and I did, too. So, how can stack pages allocated
for threads withing a single process be shared with whom?

They can RO -- so long as no one writes to them. I mean that data
is shared, frozen at spawn time. And memory can be shared but not
with writing. The memory isn't shared in any back-and-forth sense
[semaphores].

AFAIK, a thread has the spawner's stack until one of them writes
to it, then the page gets copied (CoW). You can make private
stacks, but it's more work: they have to be specially allocated
and mapped with all the usual overflow worries.

-- Robert

.

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