From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 116556 invoked by alias); 18 Sep 2016 13:55:27 -0000 Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org Received: (qmail 116536 invoked by uid 89); 18 Sep 2016 13:55:26 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=0.5 required=5.0 tests=AWL,BAYES_50,FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,RCVD_IN_SORBS_SPAM,SPF_PASS autolearn=ham version=3.3.2 spammy=201603, 2016-03, H*r:sk:gdb@sou, JIT X-HELO: mail-qk0-f171.google.com Received: from mail-qk0-f171.google.com (HELO mail-qk0-f171.google.com) (209.85.220.171) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Sun, 18 Sep 2016 13:55:16 +0000 Received: by mail-qk0-f171.google.com with SMTP id z190so126619463qkc.3 for ; Sun, 18 Sep 2016 06:55:16 -0700 (PDT) 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:from:date :message-id:subject:to:cc; bh=V/SxTQEuU2vrhgllGDf1p6ryupuVQPYiws8av/AI+0k=; b=PCyvhYNHdTL5Ju6wKd3gYlSTbT7b3vcyRxFbqttQdJTIMPG+Nk6T+EdUMGyuxJoOZ3 iyjM6ASUqxKDSWUyPGjR0pJhIrPTCPF7JXK6w7xekuNaAE/jNm1leyBYXe8plhpEj3yb ZQet6u6zq+VKIzG5W1ym9m8QurGUsB9DlqkCcmm5D2b2qlC5ndmx5qLHZn0cprO7qpvI CG9pM4S54GddZK50mZ8TceDpR7UNUBFDCHY89fV474kAFoRtmUkoKAAG5Vp/MYDxUjHV 8LMd8E+9VtjHtRYUtvC0VPG0eQI6Xk3wbnSmme0pgzkK4Qcs3AT7ITfLutn4VBrITgWy kmJA== X-Gm-Message-State: AE9vXwPqgGbM8fGa9LbrdNxwV+VbWCko7AnWLIq+UBNc817Vwb0kt8pITC6O0BKSVC+LJS9OeFY9MA6PXXsJzw== X-Received: by 10.55.54.15 with SMTP id d15mr24015532qka.262.1474206914960; Sun, 18 Sep 2016 06:55:14 -0700 (PDT) MIME-Version: 1.0 Received: by 10.233.216.130 with HTTP; Sun, 18 Sep 2016 06:54:54 -0700 (PDT) In-Reply-To: References: From: Yichao Yu Date: Sun, 18 Sep 2016 13:55:00 -0000 Message-ID: Subject: Re: Bad performance in updating JIT debug symbols To: Fredrik Tolf Cc: Duane Ellis , gdb@sourceware.org Content-Type: text/plain; charset=UTF-8 X-IsSubscribed: yes X-SW-Source: 2016-09/txt/msg00051.txt.bz2 On Sat, Sep 17, 2016 at 2:43 PM, Fredrik Tolf wrote: > On Sat, 17 Sep 2016, Duane Ellis wrote: >> >> So why not make a wrapper on the symbol lookup function >> >> Search the main list if that fails to find try the next list of syms. >> >> After you under 100 inserts resort your additional list. And start a new >> list > > > I can imagine a lot of ways to optimize the current code, but the main point > was that GDB seems to be stuck in a path of the code that is not really > intended to be used other than when GDB is "confused", so the main question > is why that happens. Ref https://sourceware.org/ml/gdb/2016-03/msg00038.html With some of my profiles and a patch that helps somewhat (there's still bad scaling) but also cause functional regression.