From: Eli Zaretskii <eliz@gnu.org>
To: Luis Machado <luis.machado@arm.com>, Tom Tromey <tom@tromey.com>
Cc: gdb-patches@sourceware.org
Subject: Re: Two observations using GDB 13 snapshot
Date: Mon, 19 Dec 2022 16:45:55 +0200 [thread overview]
Message-ID: <835ye7e9jw.fsf@gnu.org> (raw)
In-Reply-To: <c32cb97c-a189-6860-d1f0-af77a564db58@arm.com> (message from Luis Machado on Mon, 19 Dec 2022 14:08:27 +0000)
> Date: Mon, 19 Dec 2022 14:08:27 +0000
> Cc: gdb-patches@sourceware.org
> From: Luis Machado <luis.machado@arm.com>
>
> On 12/19/22 12:48, Eli Zaretskii wrote:
> > This build is without std::thread. Maybe it's related?
>
> Well, if the worker threads are disabled and things are read by a single thread, that may explain some slowness. But I don't think it would be as slow as you describe.
>
> >
> > Does GDB 13 read DWARF debug info significantly differently than
> > previous versions?
> >
> > Do you see this on GNU/Linux, when debugging GDB with itself, if you
> > disable multithreaded DWARF reading?
>
> For a regular build of GDB 13 (threaded), I see a pretty quick startup (about 3.5 seconds) to start gdb within gdb.
>
> With a GDB 13 built with threading disabled, I see about 15 seconds to do the same.
>
> Now, I noticed -readnow doesn't seem to use the worker threads for reading symbols, so passing that option slow things down significantly, to the point it takes 2 minutes to read the symbols.
>
> I don't know if that's on purpose.
Thanks.
Tom, could you please chime in? What could explain such a slowdown
using -readnow and in the MinGW build without worker threads (since
GDB 12 didn't use threads, either)? And why -readnow is so different
from a GDB built without threading?
next prev parent reply other threads:[~2022-12-19 14:45 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-12-17 17:42 Eli Zaretskii
2022-12-19 10:07 ` Luis Machado
2022-12-19 12:48 ` Eli Zaretskii
2022-12-19 14:08 ` Luis Machado
2022-12-19 14:45 ` Eli Zaretskii [this message]
2022-12-19 21:18 ` Tom Tromey
2022-12-20 3:26 ` Eli Zaretskii
2022-12-23 3:34 ` Simon Marchi
2022-12-23 8:05 ` Eli Zaretskii
2022-12-24 17:57 ` Tom Tromey
2022-12-24 18:13 ` Eli Zaretskii
2022-12-27 17:19 ` Tom Tromey
2022-12-27 18:00 ` Eli Zaretskii
2022-12-28 12:35 ` Luis Machado
2022-12-28 16:35 ` Tom Tromey
2022-12-28 17:35 ` Eli Zaretskii
2022-12-28 22:47 ` Tom Tromey
2022-12-29 15:18 ` Eli Zaretskii
2022-12-29 18:17 ` Tom Tromey
2022-12-29 18:36 ` John Baldwin
2022-12-29 19:13 ` Eli Zaretskii
2022-12-29 20:22 ` Simon Marchi
2022-12-30 14:31 ` Eli Zaretskii
2023-01-03 19:44 ` Christian Biesinger
2023-01-03 20:18 ` Eli Zaretskii
2023-01-03 20:34 ` Christian Biesinger
2023-01-03 21:34 ` Simon Marchi
2023-01-03 21:43 ` Christian Biesinger
2023-01-04 1:03 ` Tom Tromey
2023-01-04 18:10 ` Eli Zaretskii
2023-01-04 22:33 ` Tom Tromey
2023-01-05 7:11 ` Eli Zaretskii
2023-01-05 14:49 ` Christian Biesinger
2023-01-05 15:12 ` Eli Zaretskii
2023-01-06 20:55 ` Tom Tromey
2023-01-05 18:06 ` Torbjorn SVENSSON
2023-01-07 6:30 ` Eli Zaretskii
2023-01-07 9:14 ` Andreas Schwab
2023-01-07 9:32 ` Eli Zaretskii
2023-01-07 10:00 ` Andreas Schwab
2023-01-07 10:51 ` Eli Zaretskii
2023-01-07 13:04 ` Andreas Schwab
2023-01-07 13:54 ` Eli Zaretskii
2023-01-07 13:59 ` Andreas Schwab
2023-01-07 14:12 ` Eli Zaretskii
2023-01-07 14:23 ` Andreas Schwab
2023-01-07 14:29 ` Eli Zaretskii
2023-01-07 14:40 ` Andreas Schwab
2023-01-07 15:07 ` Eli Zaretskii
2023-01-07 15:40 ` Andreas Schwab
2023-01-07 16:10 ` Eli Zaretskii
2023-01-07 16:15 ` Eli Zaretskii
2023-01-07 16:16 ` Hannes Domani
2023-01-07 16:22 ` Eli Zaretskii
2023-01-07 17:39 ` Andreas Schwab
2023-01-07 18:08 ` Eli Zaretskii
2023-01-07 18:26 ` Andreas Schwab
2023-01-07 18:38 ` Eli Zaretskii
2023-01-07 19:26 ` Andreas Schwab
2023-01-07 19:35 ` Eli Zaretskii
2023-01-07 18:28 ` Hannes Domani
2023-01-07 19:25 ` Andreas Schwab
2023-01-07 15:07 ` Eli Zaretskii
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