From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 12953 invoked by alias); 17 Aug 2003 03:29:17 -0000 Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sources.redhat.com Received: (qmail 12946 invoked from network); 17 Aug 2003 03:29:17 -0000 Received: from unknown (HELO dberlin.org) (69.3.5.6) by sources.redhat.com with SMTP; 17 Aug 2003 03:29:17 -0000 Received: from [127.0.0.1] (HELO dberlin.org) by dberlin.org (CommuniGate Pro SMTP 4.1.1) with ESMTP-TLS id 4792950; Sat, 16 Aug 2003 23:29:16 -0400 Date: Sun, 17 Aug 2003 03:29:00 -0000 From: Daniel Berlin To: Daniel Jacobowitz cc: Andrew Cagney , gdb@sources.redhat.com Subject: Re: Terminally slow (75 seconds) on some steps In-Reply-To: <20030816164110.GA3818@nevyn.them.org> Message-ID: References: <3F1BF6D4.6090801@redhat.com> <3F2F3E9A.6050403@redhat.com> <3F2FF8F5.6070007@redhat.com> <3F3D65C5.2070005@redhat.com> <20030816151124.GA2746@nevyn.them.org> <3F3E5DA4.7080504@redhat.com> <20030816164110.GA3818@nevyn.them.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SW-Source: 2003-08/txt/msg00173.txt.bz2 On Sat, 16 Aug 2003, Daniel Jacobowitz wrote: > On Sat, Aug 16, 2003 at 12:36:52PM -0400, Andrew Cagney wrote: > > > > >See SYMBOL_SET_NAMES - I fixed that fairly recently. Also, > > >add_psymbol_to_list is how most partial symbols are added; that uses > > >the same name cache. If you're talking about the call to bcache in > > >add_psymbol_with_dem_name_to_list, it's only used by hpread.c. Fixing > > >this did in fact improve the hit rate. > > > > Ah. So the only bcache call is to add the partial symbol to the psymbol > > cache. That narrows things down a bit. Wonder if setting > > CHAIN_LENGTH_THRESHOLD lower would help. > > > > >>>c011f6b8 663 2.3393 vmlinux do_anonymous_page > > >>>00000000 622 2.1946 XFree86 (no symbols) > > >>>08134b74 574 2.0253 gdb read_partial_die > > > > > >> > > >>Ok, so its spending a lot of time reading partial symbols. > > > > > > > > >I've got some plans in this direction... just haven't had time to do > > >anything about it yet :( > > > > What about the kernel? 3.5 seconds copying data to the user space is > > suprising. Can linux, given page sized read requests do it using page > > swapping? > > > > The other question is where in GDB (?) the requests are comming from. I > > suspect target read, but it could be symbol file related. > > First of all, we should be using mmap to access symbol files, at least > when there are no relocations. Been there, done that, was told to do it in BFD.