From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: storm@cua.dk (Kim F. Storm) Newsgroups: gmane.emacs.devel Subject: Re: More info on sporadic OS/X crash Date: 29 Apr 2004 18:32:44 +0200 Sender: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Message-ID: References: <16527.37427.874467.884062@Ordesa.local> <2719-Wed28Apr2004205317+0300-eliz@gnu.org> <16528.61611.555662.935325@Ordesa.local> NNTP-Posting-Host: deer.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1083249498 30037 80.91.224.253 (29 Apr 2004 14:38:18 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Thu, 29 Apr 2004 14:38:18 +0000 (UTC) Cc: Eli Zaretskii , emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Thu Apr 29 16:38:05 2004 Return-path: Original-Received: from quimby.gnus.org ([80.91.224.244]) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1BJCft-0000nf-00 for ; Thu, 29 Apr 2004 16:38:05 +0200 Original-Received: from monty-python.gnu.org ([199.232.76.173]) by quimby.gnus.org with esmtp (Exim 3.35 #1 (Debian)) id 1BJCfs-0006ly-00 for ; Thu, 29 Apr 2004 16:38:04 +0200 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.30) id 1BJCbf-0003QY-7u for emacs-devel@quimby.gnus.org; Thu, 29 Apr 2004 10:33:43 -0400 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.30) id 1BJCbY-0003Q5-FI for emacs-devel@gnu.org; Thu, 29 Apr 2004 10:33:36 -0400 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.30) id 1BJCb1-0003He-3h for emacs-devel@gnu.org; Thu, 29 Apr 2004 10:33:34 -0400 Original-Received: from [212.88.64.25] (helo=mail-relay.sonofon.dk) by monty-python.gnu.org with smtp (Exim 4.30) id 1BJCb0-0003Go-CN for emacs-devel@gnu.org; Thu, 29 Apr 2004 10:33:02 -0400 Original-Received: (qmail 14190 invoked from network); 29 Apr 2004 14:33:00 -0000 Original-Received: from unknown (HELO kfs-l.imdomain.dk.cua.dk) (213.83.150.2) by 0 with SMTP; 29 Apr 2004 14:33:00 -0000 Original-To: "Piet van Oostrum" In-Reply-To: <16528.61611.555662.935325@Ordesa.local> Original-Lines: 49 User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3.50 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.4 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Xref: main.gmane.org gmane.emacs.devel:22361 X-Report-Spam: http://spam.gmane.org/gmane.emacs.devel:22361 "Piet van Oostrum" writes: > >>>>> "Eli Zaretskii" (EZ) wrote: > > >> From: "Piet van Oostrum" > >> Date: Wed, 28 Apr 2004 13:14:59 +0200 > >> > >> (gdb) frame 1 > >> #1 0x0012eeac in sys_select (n=126, rfds=0x38e7e4, wfds=0x0, efds=0x0, timeout=0xbfffc770) at mac.c:2787 > >> 2787 return select(n, rfds, wfds, efds, timeout); > >> (gdb) print *timeout > >> $3 = { > >> tv_sec = 0, > >> tv_usec = 999996 > >> } > >> > >> So this looks normal. > > EZ> Well, yes and no: how come it's 999996 microseconds instead of a full > EZ> second? That is, why don't you see this instead? > > EZ> $3 = { > EZ> tv_sec = 1, > EZ> tv_usec = 0 > EZ> } > > EZ> This higher frame in the backtrace: > > >> #2 0x00119948 in wait_reading_process_input (time_limit=1, microsecs=0, read_kbd=3506604, do_display=0) at process.c:4311 > > EZ> seems to imply that wait_reading_process_input was called to wait for > EZ> 1 second and 0 microseconds, so where from did the small inaccuracy > EZ> creep in? > > There is some code just above the select that manipulates the usecs. > (The ADAPTIVE_READ_BUFFERING stuff). But I think it always makes it a > multiple of READ_OUTPUT_DELAY_INCREMENT, which this isn't. > > Then there's also timer_delay which gets calculated from something > with the current time in it, so maybe that's it. The Linux kernel adjusts the timeout value upon return from select to contain the amount of time "remaining to the specified timeout". This is very useful in some situations. Maybe OS/X does that too. -- Kim F. Storm http://www.cua.dk