From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 30929 invoked by alias); 3 Dec 2014 00:50:15 -0000 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 Received: (qmail 30913 invoked by uid 89); 3 Dec 2014 00:50:14 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.8 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_LOW,SPF_PASS,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-HELO: mail-vc0-f174.google.com Received: from mail-vc0-f174.google.com (HELO mail-vc0-f174.google.com) (209.85.220.174) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-SHA encrypted) ESMTPS; Wed, 03 Dec 2014 00:50:13 +0000 Received: by mail-vc0-f174.google.com with SMTP id id10so6157304vcb.5 for ; Tue, 02 Dec 2014 16:50:11 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:content-type; bh=dFCeVtCc33GgxWh6hz11l+p5n13uVqoT4YW8TUtSAQs=; b=aP6/J0CbgOtHWvutLVBVSAv5c7gzpjbPWy3mdk6aw8mzaJVzd3fU28kt9UDwoNHQQp DMmIrHlxiBzR6MVgFRkUkz9+K7H+UM+Hvlo9E0aQgj7N1+enYDsknhi2eKn6i8XfMszJ yxBa5tcxGu+kK6ujq/Ep8v7ZcSsFaXph9DmebIFbMLgcI9zQwYc+gDaqVM4fsa3nME7x KVl83vKlUoBGf2VtCU6qJSNDZKhZc4KEqc8VEDKxFSIYND6wsUqK65kO2aTSr77dFsBb BvKjNteNXYj4fUSdlqspf9UWsHveBu28moN78d7uw/l71JTcIoltv/8+e84qpbQ0Dyp7 Z8wg== X-Gm-Message-State: ALoCoQkMv/Z3J20hxxO6AI6T+BtNGNN/LEYY4RNsk8FHek3s95m+wzrkyAozEBYl0wBYL3JtwOeo MIME-Version: 1.0 X-Received: by 10.52.29.84 with SMTP id i20mr785236vdh.1.1417567811152; Tue, 02 Dec 2014 16:50:11 -0800 (PST) Received: by 10.52.114.101 with HTTP; Tue, 2 Dec 2014 16:50:11 -0800 (PST) In-Reply-To: References: Date: Wed, 03 Dec 2014 00:50:00 -0000 Message-ID: Subject: Re: [RFC] symbol lookup cache From: Doug Evans To: gdb-patches , Joel Brobecker Content-Type: text/plain; charset=UTF-8 X-IsSubscribed: yes X-SW-Source: 2014-12/txt/msg00042.txt.bz2 On Mon, Dec 1, 2014 at 12:23 AM, Doug Evans wrote: > > Hi. > > Holidays are nice for having the time to take on > projects one is interested in but doesn't have > time to otherwise do. > > I looked at a couple of areas for improvement > in gdb's symbol handling over the last couple > of days. One is .gdb_index support for tab > completion, which is the topic for another mail. > This email is about a symbol lookup cache. > > ..gdb_index helps speed things up for one objfile, > but when there are 100s (or 1000s) of shared > libraries, symbol lookup can still take awhile, > even with .gdb_index. > [I'm setting aside a planned change to basic > symbol lookup to use the index better. > We'll still, I think, want a cache even > with that change.] > > This patch still needs more testing > and I need to collect more perf data, > but it's a start at caching symbol lookups. > This first pass is just for the case > where we iterate over all objfiles for > lookups in the global or static blocks. > Low hanging fruit. > At the moment it's just RFC. [bleah, sorry for the repeat Joel] One thing this patch is missing is the ability to turn the cache off, both for performance measurements and for debugging.