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From: Tom Tromey <tom@tromey.com>
To: Eli Zaretskii via Gdb-patches <gdb-patches@sourceware.org>
Cc: Luis Machado <luis.machado@arm.com>,  Tom Tromey <tom@tromey.com>,
	 Eli Zaretskii <eliz@gnu.org>
Subject: Re: Two observations using GDB 13 snapshot
Date: Mon, 19 Dec 2022 14:18:52 -0700	[thread overview]
Message-ID: <87h6xrks77.fsf@tromey.com> (raw)
In-Reply-To: <835ye7e9jw.fsf@gnu.org> (Eli Zaretskii via Gdb-patches's message of "Mon, 19 Dec 2022 16:45:55 +0200")

>>>>> "Eli" == Eli Zaretskii via Gdb-patches <gdb-patches@sourceware.org> writes:

Eli> Tom, could you please chime in?  What could explain such a slowdown
Eli> using -readnow and in the MinGW build without worker threads (since
Eli> GDB 12 didn't use threads, either)?  And why -readnow is so different
Eli> from a GDB built without threading?

Just a quick answer for now, I haven't tried to reproduce or
investigate...

-readnow should not really be affected by the DWARF scanner rewrite.
With -readnow, all the new code is bypassed anyway.  For quite a while
now, -readnow (when using DWARF anyway) has operated on the principle
that since gdb is reading full symbols, it might as well not bother with
partial symbols (or now, the index).

Threads also should not matter here, because only the initial scan can
use multiple threads.  The full symbol reader is single-threaded and
hasn't changed in any deep way since GDB 12.

It's possible that some other change affected this -- the DWARF reader
in general sees a lot of patches.  I don't know which one it might be
offhand, though.

Tom

  reply	other threads:[~2022-12-19 21:19 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
2022-12-19 21:18         ` Tom Tromey [this message]
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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