From: Dmitry Antipov <dmantipov@yandex.ru>
To: Eli Zaretskii <eliz@gnu.org>, Sebastien Vauban <sva-news@mygooglest.com>
Cc: 15876@debbugs.gnu.org
Subject: bug#15876: 24.3.50; Highly degraded performance between rev 114715 and 115006
Date: Mon, 02 Dec 2013 14:45:25 +0400 [thread overview]
Message-ID: <529C64C5.2040509@yandex.ru> (raw)
In-Reply-To: <83haas5y88.fsf@gnu.org>
On 12/01/2013 08:31 PM, Eli Zaretskii wrote:
> Dmitry, can you please look into this? I'm not familiar enough with
> the font stuff, so I don't see how was the font-spec and its
> font-entities stored in the font cache supposed to be referenced from
> some other Lisp object, to make sure they are marked and not GC'ed.
It should be easy - just use this:
=== modified file 'src/alloc.c'
--- src/alloc.c 2013-12-01 22:33:13 +0000
+++ src/alloc.c 2013-12-02 09:32:55 +0000
@@ -5731,7 +5731,18 @@
eassert (!VECTOR_MARKED_P (ptr));
VECTOR_MARK (ptr); /* Else mark it. */
if (size & PSEUDOVECTOR_FLAG)
- size &= PSEUDOVECTOR_SIZE_MASK;
+ {
+ size &= PSEUDOVECTOR_SIZE_MASK;
+ if (PSEUDOVECTOR_TYPEP (&ptr->header, PVEC_FONT))
+ {
+ Lisp_Object tmp;
+ XSETFONT (tmp, ptr);
+ if (FONT_SPEC_P (tmp))
+ fprintf (stderr, "mark font-spec\n");
+ else if (FONT_ENTITY_P (tmp))
+ fprintf (stderr, "mark font-entity\n");
+ }
+ }
and set breakpoints to fprintf(). I tried this and see that font-spec
objects can be referenced from face caches:
(gdb) bt 3 full
#0 mark_vectorlike (ptr=0x13178b8) at ../../trunk/src/alloc.c:5741
tmp = {i = 20019389}
size = 13
i = 20019389
#1 0x00000000005ec050 in mark_object (arg=...) at ../../trunk/src/alloc.c:6084
ptr = 0x13178b8
pvectype = 15
obj = {i = 20019384}
cdr_count = 0
#2 0x00000000005eb92b in mark_face_cache (c=0x15049b0) at ../../trunk/src/alloc.c:5839
face = 0x18d2050
i = 2
j = 15
(More stack frames follow...)
I.e. (struct face *)0x18d2050 has font-spec object in lface[15].
But the most of font-spec and font-entity objects are referenced via
staticpro'ed globals Vfontset_table and ft_face_cache. For example:
(gdb) bt 16
#0 mark_vectorlike (ptr=0x129a288) at ../../trunk/src/alloc.c:5741
#1 0x00000000005ec050 in mark_object (arg=...) at ../../trunk/src/alloc.c:6084
#2 0x00000000005eb5f0 in mark_vectorlike (ptr=0x1296428) at ../../trunk/src/alloc.c:5752
#3 0x00000000005ec050 in mark_object (arg=...) at ../../trunk/src/alloc.c:6084
#4 0x00000000005eb5f0 in mark_vectorlike (ptr=0x129a4d0) at ../../trunk/src/alloc.c:5752
#5 0x00000000005ec050 in mark_object (arg=...) at ../../trunk/src/alloc.c:6084
#6 0x00000000005eb725 in mark_char_table (ptr=0x1788060) at ../../trunk/src/alloc.c:5779
#7 0x00000000005eb717 in mark_char_table (ptr=0x12094d0) at ../../trunk/src/alloc.c:5776
#8 0x00000000005eb717 in mark_char_table (ptr=0x13e2578) at ../../trunk/src/alloc.c:5776
#9 0x00000000005eb717 in mark_char_table (ptr=0xd85188) at ../../trunk/src/alloc.c:5776
#10 0x00000000005ec02c in mark_object (arg=...) at ../../trunk/src/alloc.c:6069
#11 0x00000000005eb5f0 in mark_vectorlike (ptr=0xd85080) at ../../trunk/src/alloc.c:5752
#12 0x00000000005ec050 in mark_object (arg=...) at ../../trunk/src/alloc.c:6084
#13 0x00000000005eac4b in Fgarbage_collect () at ../../trunk/src/alloc.c:5489
#14 0x0000000000563500 in maybe_gc () at ../../trunk/src/lisp.h:4462
#15 0x000000000060ec3e in Ffuncall (nargs=2, args=0x7fffffff0790) at ../../trunk/src/eval.c:2756
(gdb) bt 16 full
...
#13 0x00000000005eac4b in Fgarbage_collect () at ../../trunk/src/alloc.c:5489
nextb = 0x0
stack_top_variable = 0 '\000'
i = 1491
message_p = false
count = 140
start = {tv_sec = 1385977872, tv_nsec = 656653658}
retval = {i = 13914818}
tot_before = 0
...
(gdb) p staticvec[1491]
$8 = (Lisp_Object *) 0xd25cb0 <Vfontset_table>
> In any case, it seems like they are never marked on Windows, because
> if I set a breakpoint in the line marked below:
>
> /* If font-spec is not marked, most likely all font-entities
> are not marked too. But we must be sure that nothing is
> marked within OBJ before we really drop it. */
> for (i = 0; i < size; i++)
> if (VECTOR_MARKED_P (XFONT_ENTITY (AREF (XCDR (obj), i))))
> break;
>
> if (i == size) <<<<<<<<<<<<<<<<<<<<<
> drop = 1;
> }
>
> with a condition i != size, that breakpoint never breaks.
The best way to hit this breakpoint is to run something like:
(defun bloat-font ()
(interactive)
(let ((fonts (x-list-fonts "*")))
(while fonts
(condition-case nil (set-frame-font (car fonts)) (error nil))
(setq fonts (cdr fonts))
(redisplay))))
(This is X-specific; I believe there should be a similar MS-Windows method).
Subtle "triangle example" works just fine for me (with default font used by
GTK3 build and 'emacs -Q' at least).
Also I'm curious how to reproduce this issue with X. In particular, how to
find a font so "heavy" that an attempt to load it creates a lot of Lisp data
(hundreds Kbytes, enough to reach gc_cons_threshold each time)?
Dmitry
next prev parent reply other threads:[~2013-12-02 10:45 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-12 15:32 bug#15876: 24.3.50; Highly degraded performance between rev 114715 and 115006 Sebastien Vauban
2013-11-12 17:11 ` Glenn Morris
[not found] ` <wzwqkdfsts.fsf-iW7gFb+/I3LZHJUXO5efmti2O/JbrIOy@public.gmane.org>
2013-11-12 19:13 ` Sebastien Vauban
2013-11-13 11:43 ` Dani Moncayo
[not found] ` <mailman.5954.1384343055.10748.bug-gnu-emacs@gnu.org>
2013-11-13 13:58 ` Sebastien Vauban
[not found] ` <mailman.5925.1384283656.10748.bug-gnu-emacs@gnu.org>
[not found] ` <mailman.5925.1384283656.10748.bug-gnu-emacs-mXXj517/zsQ@public.gmane.org>
2013-11-13 14:04 ` Sebastien Vauban
2013-11-13 16:11 ` Eli Zaretskii
[not found] ` <83fvr01du4.fsf-mXXj517/zsQ@public.gmane.org>
2013-11-13 20:23 ` Sebastien Vauban
2013-11-13 20:35 ` Eli Zaretskii
2013-11-14 3:05 ` Glenn Morris
[not found] ` <jxeh6j1y4x.fsf-iW7gFb+/I3LZHJUXO5efmti2O/JbrIOy@public.gmane.org>
2013-11-14 10:05 ` Sebastien Vauban
[not found] ` <mailman.6048.1384423574.10748.bug-gnu-emacs@gnu.org>
2013-11-14 10:13 ` Sebastien Vauban
2013-11-14 17:04 ` Glenn Morris
[not found] ` <mailman.6048.1384423574.10748.bug-gnu-emacs-mXXj517/zsQ@public.gmane.org>
2013-11-19 22:52 ` Sebastien Vauban
2013-11-20 1:47 ` Stefan Monnier
2013-11-20 3:53 ` Eli Zaretskii
2013-11-20 3:48 ` Eli Zaretskii
[not found] ` <mailman.6579.1384912163.10748.bug-gnu-emacs@gnu.org>
[not found] ` <mailman.6579.1384912163.10748.bug-gnu-emacs-mXXj517/zsQ@public.gmane.org>
2013-11-20 8:48 ` Sebastien Vauban
[not found] ` <mailman.6575.1384901595.10748.bug-gnu-emacs@gnu.org>
[not found] ` <mailman.6575.1384901595.10748.bug-gnu-emacs-mXXj517/zsQ@public.gmane.org>
2013-11-20 22:32 ` Sebastien Vauban
2013-11-21 3:42 ` Eli Zaretskii
[not found] ` <mailman.6739.1385005456.10748.bug-gnu-emacs@gnu.org>
[not found] ` <mailman.6739.1385005456.10748.bug-gnu-emacs-mXXj517/zsQ@public.gmane.org>
2013-11-26 20:52 ` Sebastien Vauban
2013-11-26 21:04 ` Eli Zaretskii
[not found] ` <mailman.7212.1385499914.10748.bug-gnu-emacs@gnu.org>
[not found] ` <mailman.7212.1385499914.10748.bug-gnu-emacs-mXXj517/zsQ@public.gmane.org>
2013-11-29 21:01 ` Sebastien Vauban
2013-12-01 16:31 ` Eli Zaretskii
2013-12-02 10:45 ` Dmitry Antipov [this message]
2013-12-02 11:43 ` Dmitry Antipov
2013-12-02 18:00 ` Eli Zaretskii
2013-12-02 17:52 ` Eli Zaretskii
2013-12-03 9:57 ` Dmitry Antipov
2013-12-03 13:16 ` Eli Zaretskii
2013-12-03 15:09 ` Dmitry Antipov
2013-12-04 17:53 ` Eli Zaretskii
2013-12-05 6:29 ` Dmitry Antipov
2013-12-05 17:36 ` Eli Zaretskii
2013-12-11 6:52 ` Dmitry Antipov
2013-12-11 7:16 ` bug#15876: [SPAM] " Jarek Czekalski
2013-12-11 9:24 ` Dmitry Antipov
2013-12-11 16:28 ` Eli Zaretskii
2013-12-11 18:00 ` Dmitry Antipov
2013-12-11 18:12 ` Eli Zaretskii
2013-12-11 19:50 ` Jan Djärv
2013-12-13 15:22 ` Eli Zaretskii
2013-12-13 16:12 ` Dmitry Antipov
2013-12-13 16:45 ` Stefan Monnier
2013-12-13 18:53 ` Eli Zaretskii
2013-12-13 18:44 ` Eli Zaretskii
2013-12-16 8:05 ` Dmitry Antipov
2013-12-13 16:50 ` Stefan Monnier
2013-12-13 18:55 ` Eli Zaretskii
2013-12-14 2:13 ` Stefan Monnier
2013-12-14 8:47 ` Jan Djärv
[not found] ` <mailman.7746.1385915595.10748.bug-gnu-emacs@gnu.org>
[not found] ` <mailman.7746.1385915595.10748.bug-gnu-emacs-mXXj517/zsQ@public.gmane.org>
2013-12-01 20:20 ` Sebastien Vauban
2013-12-01 20:37 ` Eli Zaretskii
[not found] ` <mailman.7763.1385930292.10748.bug-gnu-emacs@gnu.org>
[not found] ` <mailman.7763.1385930292.10748.bug-gnu-emacs-mXXj517/zsQ@public.gmane.org>
2013-12-01 21:51 ` Sebastien Vauban
2013-12-02 3:45 ` Eli Zaretskii
[not found] ` <mailman.7786.1385955973.10748.bug-gnu-emacs@gnu.org>
[not found] ` <mailman.7786.1385955973.10748.bug-gnu-emacs-mXXj517/zsQ@public.gmane.org>
2013-12-02 9:29 ` Sebastien Vauban
2013-11-13 16:52 ` Stefan Monnier
2013-11-14 11:03 ` Jarek Czekalski
2013-11-14 16:35 ` Eli Zaretskii
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=529C64C5.2040509@yandex.ru \
--to=dmantipov@yandex.ru \
--cc=15876@debbugs.gnu.org \
--cc=eliz@gnu.org \
--cc=sva-news@mygooglest.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this external index
https://git.savannah.gnu.org/cgit/emacs.git
https://git.savannah.gnu.org/cgit/emacs/org-mode.git
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.