tech-kern archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: vmem(9) (was Re: netbsd-6: pagedaemon freeze when low on memory)



Thor Lancelot Simon <tls%panix.com@localhost> writes:

> On Tue, Mar 19, 2013 at 06:55:54PM -0400, Greg Troxel wrote:
>> 
>> Thor Lancelot Simon <tls%panix.com@localhost> writes:
>> 
>> > I think pools should be (slightly) leaky buckets.
>> 
>> So do you mean that pools should free a page every so often if it's
>> available, so that a pool's usage of unallocated pages decays as
>> e^-(t/60s), or something like that?
>
> Yes.  Just like that.  I think it might keep a number of common
> cyclical workloads from becoming pathological so that they end
> up trying to aggressively drain.

I think it's a reasonable suggestion for experimentation.  It's an open
question whether it will be more efficient overall, since draining
without pressure will lead to less object reuse.

I don't think you meant to suggest that this should be the only
mechanism; it seems that pressure will arise (due to workloads) and thus
the drain stuff needs to be right regardless.

Attachment: pgpZeQW5EXpas.pgp
Description: PGP signature



Home | Main Index | Thread Index | Old Index