Re: VFS reclaims are scarce on netbsd-6

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Fri, Apr 13, 2012 at 05:15:39PM +0200, Emmanuel Dreyfus wrote:
> Thor Lancelot Simon <tls%panix.com@localhost> wrote:
> 
> > So what?  If the memory is wanted for something else, it will be
> > reclaimed.  How does this differ from any other filesystem?  In
> > fact, this memory seems to me more likely to be effectively reclaimed
> > than that holding other vnodes, because (unless you've done something
> > to stop it) the server process is, unlike in-kernel holders of vnodes,
> > eligible to be paged...
> 
> But that means perfused needs to get unlimited rlimits for RLIMIT_AS and
> RLIMIT_DATA (and perhaps RLIMIT_RSS?). Is that acceptable?

Are you telling me that perfused has no way to tell the kernel to
invalidate one of its vnodes?

If so, this seems like an interface design mistake.

Otherwise, it seems to me that if perfused has a limited amount of memory
to work with, it needs to decide how many vnodes to keep around itself,
rather than hoping the kernel will happen to do the right thing for it.

Thor