From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 9264 invoked by alias); 1 Sep 2009 02:32:21 -0000 Received: (qmail 9252 invoked by uid 22791); 1 Sep 2009 02:32:19 -0000 X-SWARE-Spam-Status: No, hits=-1.8 required=5.0 tests=AWL,BAYES_00,J_CHICKENPOX_37,SPF_PASS X-Spam-Check-By: sourceware.org Received: from smtp-out.google.com (HELO smtp-out.google.com) (216.239.33.17) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 01 Sep 2009 02:32:14 +0000 Received: from wpaz5.hot.corp.google.com (wpaz5.hot.corp.google.com [172.24.198.69]) by smtp-out.google.com with ESMTP id n812W9eb027647; Tue, 1 Sep 2009 03:32:09 +0100 Received: from localhost (ruffy.mtv.corp.google.com [172.18.118.116]) by wpaz5.hot.corp.google.com with ESMTP id n812W6CI013236; Mon, 31 Aug 2009 19:32:07 -0700 Received: by localhost (Postfix, from userid 67641) id C5DDD843B8; Mon, 31 Aug 2009 19:32:06 -0700 (PDT) To: eliz@gnu.org, gdb-patches@sourceware.org Subject: [RFA] Addition to docs, non-stop mode vs remote caching Message-Id: <20090901023206.C5DDD843B8@localhost> Date: Tue, 01 Sep 2009 02:32:00 -0000 From: dje@google.com (Doug Evans) X-System-Of-Record: true X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2009-09/txt/msg00003.txt.bz2 [resend, typo in address] Hi. Ok to check in? 2009-08-31 Doug Evans * gdb.texinfo (Caching Data of Remote Targets): Add note on non-stop mode's affect on remote caching. Index: doc/gdb.texinfo =================================================================== RCS file: /cvs/src/src/gdb/doc/gdb.texinfo,v retrieving revision 1.619 diff -u -p -r1.619 gdb.texinfo --- doc/gdb.texinfo 31 Aug 2009 20:18:46 -0000 1.619 +++ doc/gdb.texinfo 1 Sep 2009 02:26:36 -0000 @@ -8427,8 +8427,14 @@ performance, because it reduces the over bundling memory reads and writes into large chunks. Unfortunately, simply caching everything would lead to incorrect results, since @value{GDBN} does not necessarily know anything about volatile values, memory-mapped I/O -addresses, etc. Therefore, by default, @value{GDBN} only caches data -known to be on the stack. Other regions of memory can be explicitly marked +addresses, etc. Furthermore, in non-stop mode (@pxref{Non-Stop Mode}) +memory can be changed @emph{while} a gdb command is executing. +Therefore, by default, @value{GDBN} only caches data +known to be on the stack.@footnote{In non-stop mode, it is moderately +rare for a running thread to modify the stack of a stopped thread +in a way that would interfere with a backtrace, and caching of +stack reads provides a significant speed up of remote backtraces.} +Other regions of memory can be explicitly marked cacheable; see @pxref{Memory Region Attributes}. @table @code