GNU bug report logs - #61489
[PATCH 1/1] Increase BLOCK_ALIGN from 2¹⁰to 2¹⁵

Previous Next

Full log

View this message in rfc822 format

From: help-debbugs <at> gnu.org (GNU bug Tracking System)
To: Konstantin Kharlamov <Hi-Angel <at> yandex.ru>
Subject: bug#61489: closed (Re: bug#61489: [PATCH v2] Increase BLOCK_ALIGN
 from 1024 to 32768)
Date: Sat, 04 Mar 2023 11:28:02 +0000

[Message part 1 (text/plain, inline)]

Your bug report

#61489: [PATCH 1/1] Increase BLOCK_ALIGN from 2¹⁰to 2¹⁵

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 61489 <at> debbugs.gnu.org.

-- 
61489: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=61489
GNU Bug Tracking System
Contact help-debbugs <at> gnu.org with problems

[Message part 2 (message/rfc822, inline)]

From: Eli Zaretskii <eliz <at> gnu.org>
To: Konstantin Kharlamov <Hi-Angel <at> yandex.ru>
Cc: 61489-done <at> debbugs.gnu.org
Subject: Re: bug#61489: [PATCH v2] Increase BLOCK_ALIGN from 1024 to 32768
Date: Sat, 04 Mar 2023 13:26:58 +0200

> From: Konstantin Kharlamov <Hi-Angel <at> yandex.ru>
> Date: Thu, 16 Feb 2023 18:07:55 +0300
> 
> Originally discovered by Tyler Dodge in his article "Significant Garbage
> Collection Improvement For Emacs".
> 
> While testing this change on Archlinux system with Intel i5-7200U CPU,
> average time of garbage collection gets reduced by ≈25%. Other users
> report improvements up to 50%. While monitoring PSS of emacs with and
> without customizations loaded before and after the patch, no
> statistically significant differences were discovered. So overall, this
> change is a win.
> 
> * src/alloc.c (BLOCK_ALIGN): increase from 1024 to 32768

Thanks, installed on the master branch, and closing the bug.

[Message part 3 (message/rfc822, inline)]

From: Konstantin Kharlamov <Hi-Angel <at> yandex.ru>
To: bug-gnu-emacs <at> gnu.org
Subject: [PATCH 1/1] Increase BLOCK_ALIGN from 2¹⁰to 2¹⁵
Date: Mon, 13 Feb 2023 23:00:06 +0300

Originally discovered by Tyler Dodge in his article "Significant Garbage
Collection Improvement For Emacs".

While testing this change on Archlinux system with Intel i5-7200U CPU,
average time of garbage collection gets reduced by ≈25%. While
monitoring PSS of emacs with and without customizations loaded before
and after the patch, no statistically significant differences were
discovered. So overall, this change is a win.

* src/alloc.c (BLOCK_ALIGN): increase from 2¹⁰ to 2¹⁵
---
 src/alloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/alloc.c b/src/alloc.c
index c25e81d1dde..d278b01343d 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -1083,7 +1083,7 @@ lisp_free (void *block)
    BLOCK_BYTES and guarantees they are aligned on a BLOCK_ALIGN boundary.  */
 
 /* Byte alignment of storage blocks.  */
-#define BLOCK_ALIGN (1 << 10)
+#define BLOCK_ALIGN (1 << 15)
 verify (POWER_OF_2 (BLOCK_ALIGN));
 
 /* Use aligned_alloc if it or a simple substitute is available.
-- 
2.39.0

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.