Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 14 Oct 2005 15:19:19 -0400 (EDT)
From:      Andrew Gallatin <gallatin@cs.duke.edu>
To:        "Poul-Henning Kamp" <phk@phk.freebsd.dk>
Cc:        Garrett Wollman <wollman@csail.mit.edu>, net@FreeBSD.org
Subject:   Re: Call for performance evaluation: net.isr.direct (fwd) 
Message-ID:  <17232.1207.615226.432579@grasshopper.cs.duke.edu>
In-Reply-To: <31823.1129304673@critter.freebsd.dk>
References:  <17231.50841.442047.622878@grasshopper.cs.duke.edu> <31823.1129304673@critter.freebsd.dk>

next in thread | previous in thread | raw e-mail | index | archive | help

Poul-Henning Kamp writes:
 > The solution is not faster but less reliable timekeeping, the
 > solution is to move the scheduler(s) away from using time as an
 > approximation of cpu cycles.

So you mean rather than use binuptime() in mi_switch(), use some
per-cpu cycle counter (like rdtsc)?

Heck, why not just use ticks for the scheduler and keep the expensive
timekeeping code out of the critical path altogether?  Does it really
need better than 1ms resolution?

Drew



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?17232.1207.615226.432579>