Re: Virtual memory consumption (both user and kernel) inmodern CURRENT

On 2/17/06, Brian K. White <brian_at_aljex.com> wrote:
>
> ----- Original Message -----
> From: "Mike Jakubik" <mikej_at_rogers.com>
> To: "Kris Kennaway" <kris_at_obsecurity.org>
> Cc: "Giorgos Keramidas" <keramida_at_ceid.upatras.gr>; "Dmitry Pryanishnikov"
> <dmitry_at_atlantis.dp.ua>; <freebsd-current_at_freebsd.org>; "David Xu"
> <davidxu_at_freebsd.org>; "Brian Candler" <B.Candler_at_pobox.com>
> Sent: Friday, February 17, 2006 1:34 PM
> Subject: Re: Virtual memory consumption (both user and kernel) inmodern
> CURRENT
>
>
> > Kris Kennaway wrote:
> >> On Thu, Feb 16, 2006 at 08:23:50PM -0500, Mike Jakubik wrote:
> >>
> >>> And what am i trading off here? I have "/etc/malloc.conf_at_ -> ajz" and my
> >>> memory usage has gone up the roof. My system used to be swap free, and
> >>> now its swapping over 40 MB. Can someone explain to me why this new
> >>> malloc is better? I don't see any speed improvements.
> >>>
> >>
> >> It's a couple of orders of magnitude faster for threaded binaries.
> >> See earlier posts by the author for extensive discussion.
> >>
> >
> > Great, too bad only 2% of my applications are threaded. I just don't see
> > this change very positively, using 40MB of swap, where before was none
> > does not seem to me like a speed improvement. I'm all for better
> > performance of threaded apps, but the trade off seems too high.
>
> Especially if: What's orders of magnitude faster, the main parts of the app
> or merely the act of spawning/destroying a new thread?

Logically, since this is a malloc implementation one could infer that
it's "malloc" and "free" that end up orders of magnitude faster due to
less locking and dedicated per-thread memory arenas.

At least that's my deduction.  I hope I'm correct :).

Dave