Re: [RFC 00/14] Dynamic Kernel Stacks

[Pasha Tatashin]

> >
> > My point is that what matters is total memory use, not just memory used in
> > the kernel. Amdahl's law.
>
> If userspace is running a few processes with many threads and the
> userspace stacks are small, kernel stacks could end up dominating.
>
> I'd like to see some numbers though.

The unused kernel stack pages occupy petabytes of memory across the fleet [1].

I also submitted a patch [2] that can help visualize the maximum stack
page access distribution.

[1] https://lore.kernel.org/all/CA+CK2bBYt9RAVqASB2eLyRQxYT5aiL0fGhUu3TumQCyJCNTWvw@xxxxxxxxxxxxxx
[2] https://lore.kernel.org/all/20240314145457.1106299-1-pasha.tatashin@xxxxxxxxxx