From owner-freebsd-chat Wed Oct 25 14:36:51 2000 Delivered-To: freebsd-chat@freebsd.org Received: from prism.flugsvamp.com (cb58709-a.mdsn1.wi.home.com [24.17.241.9]) by hub.freebsd.org (Postfix) with ESMTP id DC58537B479 for ; Wed, 25 Oct 2000 14:36:48 -0700 (PDT) Received: (from jlemon@localhost) by prism.flugsvamp.com (8.11.0/8.11.0) id e9PLZCc87745; Wed, 25 Oct 2000 16:35:12 -0500 (CDT) (envelope-from jlemon) Date: Wed, 25 Oct 2000 16:35:12 -0500 From: Jonathan Lemon To: Jamie Lokier Cc: Simon Kirby , Jonathan Lemon , Dan Kegel , chat@freebsd.org, linux-kernel@vger.kernel.org Subject: Re: kqueue microbenchmark results Message-ID: <20001025163512.A87091@prism.flugsvamp.com> References: <20001024225637.A54554@prism.flugsvamp.com> <39F6655A.353FD236@alumni.caltech.edu> <20001025010246.B57913@prism.flugsvamp.com> <20001025112709.A1500@stormix.com> <20001025122307.B78130@prism.flugsvamp.com> <20001025114028.F12064@stormix.com> <20001025214053.C3685@pcep-jamie.cern.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0pre2i In-Reply-To: <20001025214053.C3685@pcep-jamie.cern.ch> Sender: owner-freebsd-chat@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Wed, Oct 25, 2000 at 09:40:53PM +0200, Jamie Lokier wrote: > Simon Kirby wrote: > > And you'd need to take the descriptor out of the read() set in the > > select() case anyway, so I don't really see what's different. > > The difference is that taking a bit out of select()'s bitmap is > basically free. Whereas the equivalent with events is a bind_event() > system call. With the caveat that kevent() will take a changelist at the same time that it returns an eventlist, so while you do incur some kernel processing to temporarily disable the descriptor, the system call is essentially free. -- Jonathan To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-chat" in the body of the message