bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Alexander Asteroth]

Dear all,

my emacs hangs pretty often anf for 10 secs. ca. when I am prompted for
e.g. a file in find-file, or an interactive function in M-x or a
shell-command in read-shell-command. It seems to happen only, in these
cases, when there is an option to auto-complete. It appears particularly
often right after emacs was started (and even multiple times). After
emacs runs for hours or even days the problem is very rare.

I tried stracing my emacs (wich is a little problematic, since it is
also my window manager) and killing the strace/emacs/exwm right after
the hanging happens it always appeared right after a strace fragment
like this:

     0.000733 recvmsg(6, 0x7ffdfdb31430, 0) = -1 EAGAIN (Resource temporarily unavailable)
     0.000273 poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 0 (Timeout)
     0.000230 poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 0 (Timeout)
     0.000435 poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 0 (Timeout)
     0.000202 poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 0 (Timeout)
     0.000288 poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 0 (Timeout)
     0.000177 poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 0 (Timeout)
     0.000390 poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 0 (Timeout)
     0.000159 poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 0 (Timeout)
     0.000199 recvmsg(6, 0x7ffdfdb31430, 0) = -1 EAGAIN (Resource temporarily unavailable)
     0.000158 poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 0 (Timeout)
     0.000148 recvmsg(6, 0x7ffdfdb31650, 0) = -1 EAGAIN (Resource temporarily unavailable)
     0.000086 poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 0 (Timeout)
     0.000117 pselect6(15, [4 6 7 10 12 13 14], [], NULL, {1, 911848155}, {NULL, 8}) = 1 (in [4], left {1, 4014190})
     0.908089 read(4, "\1\0\0\0\0\0\0\0", 8) = 8
     0.000229 pselect6(15, [4 6 7 10 12 13 14], [], NULL, {1, 3617217},     {NULL, 8}

I suspected the read(4, ....) call since it always appears near the end,
but then tried also stracing emacs -Q and a) it does not seem to have
the hanging problem and b) it also containes these reads, that take 0.4
to 0.9 seconds.

Any suggestion how I could narrow down the cause of this problem?

Thanks,

        Alex

--------------------------------------------------



In GNU Emacs 26.0.50.1 (x86_64-pc-linux-gnu, GTK+ Version 3.18.9)
 of 2016-10-23 built on epsilon
Repository revision: 8ca70e402ecab5d7e71e418af6866c8b02d4f757
Windowing system distributor 'The X.Org Foundation', version 11.0.11804000
System Description:	Ubuntu 16.04.3 LTS

Recent messages:
221 2.0.0 ux-2s11.inf.fh-bonn-rhein-sieg.de closing connection
Mark set
Saving file /$HOME/mail/maildir/sent/cur/1503128660.60aa4ae141fa26ab.epsilon:2,S...
Wrote /$HOME/mail/maildir/sent/cur/1503128660.60aa4ae141fa26ab.epsilon:2,S
Sending...done
[mu4e] Message sent
Decrypting /$HOME/... done
Making completion list... [2 times]
user-error: Beginning of history; no preceding item
user-error: End of history; no default available
Quit [3 times]
Configured using:
 'configure --with-xwidgets'

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND GPM DBUS GCONF GSETTINGS
NOTIFY ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK3 X11 XWIDGETS

Important settings:
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  locale-coding-system: utf-8-unix

Major mode: Text

Minor modes in effect:
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bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Eli Zaretskii]

> From: Alexander Asteroth <alexander.asteroth@h-brs.de>
> Date: Sat, 19 Aug 2017 09:50:44 +0200
> 
> I suspected the read(4, ....) call since it always appears near the end,
> but then tried also stracing emacs -Q and a) it does not seem to have
> the hanging problem and b) it also containes these reads, that take 0.4
> to 0.9 seconds.
> 
> Any suggestion how I could narrow down the cause of this problem?

If "emacs" hangs, but "emacs -Q" doesn't, then how about bisecting
your init file to find the customization(s) that cause these hangs?

One other thing to try is start the profiler (M-x profiler-start), do
whatever it takes to cause the hang, then type M-x profiler-report,
expand all the branches in the tree it presents and post the result
here.  This could give a hint about the package/feature which causes
this.

Thanks.

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Alexander Asteroth]

Hi Eli,

I tried and after bisection after bisection, hangs got less but did not
disappear. Then I did one final test with emacs -Q again and actually
managed, after several minutes, a hanging as well, after find-file with
completion in buffers with lots of files in it (/usr/share/... or
similar).

I come to the conclusion, that it probably is not an emacs problem at
all but rather a hardware or OS problem that manifests only in a singe
threaded application like emacs.

... the search continues ...

-- Alex

Eli Zaretskii writes:

>> From: Alexander Asteroth <alexander.asteroth@h-brs.de>
>> Date: Sat, 19 Aug 2017 09:50:44 +0200
>>
>> I suspected the read(4, ....) call since it always appears near the end,
>> but then tried also stracing emacs -Q and a) it does not seem to have
>> the hanging problem and b) it also containes these reads, that take 0.4
>> to 0.9 seconds.
>>
>> Any suggestion how I could narrow down the cause of this problem?
>
> If "emacs" hangs, but "emacs -Q" doesn't, then how about bisecting
> your init file to find the customization(s) that cause these hangs?
>
> One other thing to try is start the profiler (M-x profiler-start), do
> whatever it takes to cause the hang, then type M-x profiler-report,
> expand all the branches in the tree it presents and post the result
> here.  This could give a hint about the package/feature which causes
> this.
>
> Thanks.

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Eli Zaretskii]

> From: Alexander Asteroth <alexander.asteroth@h-brs.de>
> Cc: Alexander Asteroth <alexander.asteroth@h-brs.de>, 28149@debbugs.gnu.org
> Date: Mon, 21 Aug 2017 09:07:05 +0200
> 
> I tried and after bisection after bisection, hangs got less but did not
> disappear. Then I did one final test with emacs -Q again and actually
> managed, after several minutes, a hanging as well, after find-file with
> completion in buffers with lots of files in it (/usr/share/... or
> similar).
> 
> I come to the conclusion, that it probably is not an emacs problem at
> all but rather a hardware or OS problem that manifests only in a singe
> threaded application like emacs.

Hmm.  This description is not entirely consistent with your original
report, which said:

> my emacs hangs pretty often anf for 10 secs. ca. when I am prompted for
> e.g. a file in find-file, or an interactive function in M-x or a
> shell-command in read-shell-command. It seems to happen only, in these
> cases, when there is an option to auto-complete.

This doesn't sound like the hangs were while Emacs was actually
auto-completing on file names.  Was that just an inaccuracy in the
description, and you in fact see the hangs only while Emacs completes
on file names, after you type TAB etc.?

In any case, 10 sec for completion sounds like a lot to me.
Especially since yours looks like an optimized build.  How many files
do you have in the directory where completion is so slow?  And what
kind of CPU do you have on that system?

Thanks.

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Alexander Asteroth]

Eli Zaretskii writes:
>> I tried and after bisection after bisection, hangs got less but did not
>> disappear. Then I did one final test with emacs -Q again and actually
>> managed, after several minutes, a hanging as well, after find-file with
>> completion in buffers with lots of files in it (/usr/share/... or
>> similar).
>>
>> I come to the conclusion, that it probably is not an emacs problem at
>> all but rather a hardware or OS problem that manifests only in a singe
>> threaded application like emacs.
>
> Hmm.  This description is not entirely consistent with your original
> report, which said:
>
>> my emacs hangs pretty often anf for 10 secs. ca. when I am prompted for
>> e.g. a file in find-file, or an interactive function in M-x or a
>> shell-command in read-shell-command. It seems to happen only, in these
>> cases, when there is an option to auto-complete.

Not inconsistend but there seems to be a gradual decrease in the
frequency this happens (depending on the size of my init.el). With emacs
-Q it happens so rarely, I have to change folder and complete very
often.

>
> This doesn't sound like the hangs were while Emacs was actually
> auto-completing on file names.  Was that just an inaccuracy in the
> description, and you in fact see the hangs only while Emacs completes
> on file names, after you type TAB etc.?
>
> In any case, 10 sec for completion sounds like a lot to me.
> Especially since yours looks like an optimized build.  How many files
> do you have in the directory where completion is so slow?  And what
> kind of CPU do you have on that system?

I also tried emacs 25.2 with the same result. System is a 1 year old
Lenovo ThinkPad Yoga 260.

As I said I'm not really sure any more it is emacs. What is particularly
surprising is the huge difference between read on file descriptor 3 and 
4. fd 3 take 0.00002 on average, fd 4 takes 0.4 to 0.9 seconds.

-- Alex

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Alexander Asteroth]

Hi all,

the source of error seems to be related to the graphics driver. Hangs
are related to these lines in syslog/dmesg:

--------------------
[63129.201509] [drm] stuck on render ring
[63129.201808] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [8965], reason: Engine(s) hung, action: reset
[63129.203624] drm/i915: Resetting chip after gpu hang
[63131.202095] [drm] RC6 on
-------------------

which seem to be temporarly related to the error. Some Tickets about this
error are already open in freedesktop.org by other users. Let's hope
there will be a workaround.

PS: I don't have a clue why this happens when autocompleting in emacs :-/

-- Alex

Alexander Asteroth writes:

> Eli Zaretskii writes:
>>> I tried and after bisection after bisection, hangs got less but did not
>>> disappear. Then I did one final test with emacs -Q again and actually
>>> managed, after several minutes, a hanging as well, after find-file with
>>> completion in buffers with lots of files in it (/usr/share/... or
>>> similar).
>>>
>>> I come to the conclusion, that it probably is not an emacs problem at
>>> all but rather a hardware or OS problem that manifests only in a singe
>>> threaded application like emacs.
>>
>> Hmm.  This description is not entirely consistent with your original
>> report, which said:
>>
>>> my emacs hangs pretty often anf for 10 secs. ca. when I am prompted for
>>> e.g. a file in find-file, or an interactive function in M-x or a
>>> shell-command in read-shell-command. It seems to happen only, in these
>>> cases, when there is an option to auto-complete.
>
> Not inconsistend but there seems to be a gradual decrease in the
> frequency this happens (depending on the size of my init.el). With emacs
> -Q it happens so rarely, I have to change folder and complete very
> often.
>
>>
>> This doesn't sound like the hangs were while Emacs was actually
>> auto-completing on file names.  Was that just an inaccuracy in the
>> description, and you in fact see the hangs only while Emacs completes
>> on file names, after you type TAB etc.?
>>
>> In any case, 10 sec for completion sounds like a lot to me.
>> Especially since yours looks like an optimized build.  How many files
>> do you have in the directory where completion is so slow?  And what
>> kind of CPU do you have on that system?
>
> I also tried emacs 25.2 with the same result. System is a 1 year old
> Lenovo ThinkPad Yoga 260.
>
> As I said I'm not really sure any more it is emacs. What is particularly
> surprising is the huge difference between read on file descriptor 3 and 
> 4. fd 3 take 0.00002 on average, fd 4 takes 0.4 to 0.9 seconds.
>
> -- Alex


-- 
Viele Grüße,

	Alex

--------------------------------------------------------------------------
Prof. Dr. Alexander Asteroth   		  room A.022.3
Fon:  +49 2241 865 255                    Bonn-Rhein-Sieg University o.a.s.
Fax:  +49 2241 865 8255                   Computer Science Department
mail: alexander.asteroth@h-brs.de         Grantham-Allee 20
Web:  http://www.inf.h-brs.de/asteroth    53757 Sankt Augustin, Germany

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Alexander Asteroth]

Hi all,

the source of error seems to be related to the graphics driver. Hangs
are related to these lines in syslog/dmesg:

--------------------
[63129.201509] [drm] stuck on render ring
[63129.201808] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [8965], reason: Engine(s) hung, action: reset
[63129.203624] drm/i915: Resetting chip after gpu hang
[63131.202095] [drm] RC6 on
-------------------

which seem to be temporarly related to the error. Some Tickets about this
error are already open in freedesktop.org by other users. Let's hope
there will be a workaround.

PS: I don't have a clue why this happens when autocompleting in emacs :-/

-- Alex

Alexander Asteroth writes:

> Eli Zaretskii writes:
>>> I tried and after bisection after bisection, hangs got less but did not
>>> disappear. Then I did one final test with emacs -Q again and actually
>>> managed, after several minutes, a hanging as well, after find-file with
>>> completion in buffers with lots of files in it (/usr/share/... or
>>> similar).
>>>
>>> I come to the conclusion, that it probably is not an emacs problem at
>>> all but rather a hardware or OS problem that manifests only in a singe
>>> threaded application like emacs.
>>
>> Hmm.  This description is not entirely consistent with your original
>> report, which said:
>>
>>> my emacs hangs pretty often anf for 10 secs. ca. when I am prompted for
>>> e.g. a file in find-file, or an interactive function in M-x or a
>>> shell-command in read-shell-command. It seems to happen only, in these
>>> cases, when there is an option to auto-complete.
>
> Not inconsistend but there seems to be a gradual decrease in the
> frequency this happens (depending on the size of my init.el). With emacs
> -Q it happens so rarely, I have to change folder and complete very
> often.
>
>>
>> This doesn't sound like the hangs were while Emacs was actually
>> auto-completing on file names.  Was that just an inaccuracy in the
>> description, and you in fact see the hangs only while Emacs completes
>> on file names, after you type TAB etc.?
>>
>> In any case, 10 sec for completion sounds like a lot to me.
>> Especially since yours looks like an optimized build.  How many files
>> do you have in the directory where completion is so slow?  And what
>> kind of CPU do you have on that system?
>
> I also tried emacs 25.2 with the same result. System is a 1 year old
> Lenovo ThinkPad Yoga 260.
>
> As I said I'm not really sure any more it is emacs. What is particularly
> surprising is the huge difference between read on file descriptor 3 and 
> 4. fd 3 take 0.00002 on average, fd 4 takes 0.4 to 0.9 seconds.
>
> -- Alex


-- 
Viele Grüße,

	Alex

--------------------------------------------------------------------------
Prof. Dr. Alexander Asteroth   		  room A.022.3
Fon:  +49 2241 865 255                    Bonn-Rhein-Sieg University o.a.s.
Fax:  +49 2241 865 8255                   Computer Science Department
mail: alexander.asteroth@h-brs.de         Grantham-Allee 20
Web:  http://www.inf.h-brs.de/asteroth    53757 Sankt Augustin, Germany

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Eli Zaretskii]

> From: Alexander Asteroth <alexander.asteroth@h-brs.de>
> Cc: Eli Zaretskii <eliz@gnu.org>, 28149@debbugs.gnu.org
> Date: Tue, 22 Aug 2017 18:33:27 +0200
> 
> the source of error seems to be related to the graphics driver. Hangs
> are related to these lines in syslog/dmesg:
> 
> --------------------
> [63129.201509] [drm] stuck on render ring
> [63129.201808] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [8965], reason: Engine(s) hung, action: reset
> [63129.203624] drm/i915: Resetting chip after gpu hang
> [63131.202095] [drm] RC6 on
> -------------------
> 
> which seem to be temporarly related to the error. Some Tickets about this
> error are already open in freedesktop.org by other users. Let's hope
> there will be a workaround.

Thanks for letting us know.  I guess we can now close this bug, then?

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Alexander Asteroth]

Eli Zaretskii writes:

>> From: Alexander Asteroth <alexander.asteroth@h-brs.de>
>> Cc: Eli Zaretskii <eliz@gnu.org>, 28149@debbugs.gnu.org
>> Date: Tue, 22 Aug 2017 18:33:27 +0200
>> 
>> the source of error seems to be related to the graphics driver. Hangs
>> are related to these lines in syslog/dmesg:
>> 
>> --------------------
>> [63129.201509] [drm] stuck on render ring
>> [63129.201808] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [8965], reason: Engine(s) hung, action: reset
>> [63129.203624] drm/i915: Resetting chip after gpu hang
>> [63131.202095] [drm] RC6 on
>> -------------------
>> 
>> which seem to be temporarly related to the error. Some Tickets about this
>> error are already open in freedesktop.org by other users. Let's hope
>> there will be a workaround.
>
> Thanks for letting us know.  I guess we can now close this bug, then?

Yes! Thanks for you help in that matter.

Cheers,

        Alex

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Alexander Asteroth]

Dear Eli,

maybe it is to early to close the ticket.
Right now I did the following eperiment:

open /var/log/syslog
C-x C-f
Backspace
C-f

first C-x C-f opens ido-find-file
second C-f opens find-file

This produced reproducable GPU Hangs. See following syslog (no lines cut
out)

--------------------------------------
Aug 22 22:38:33 epsilon kernel: [90414.610167] [drm] stuck on render ring
Aug 22 22:38:33 epsilon kernel: [90414.610499] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [21887], reason: Engine(s) hung, action: reset
Aug 22 22:38:33 epsilon kernel: [90414.612283] drm/i915: Resetting chip after gpu hang
Aug 22 22:38:35 epsilon kernel: [90416.611033] [drm] RC6 on
Aug 22 22:40:00 epsilon kernel: [90501.610885] [drm] stuck on render ring
Aug 22 22:40:00 epsilon kernel: [90501.611184] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [21887], reason: Engine(s) hung, action: reset
Aug 22 22:40:00 epsilon kernel: [90501.613000] drm/i915: Resetting chip after gpu hang
Aug 22 22:40:02 epsilon kernel: [90503.611308] [drm] RC6 on
Aug 22 22:40:24 epsilon kernel: [90525.599079] [drm] stuck on render ring
Aug 22 22:40:24 epsilon kernel: [90525.599394] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [21887], reason: Engine(s) hung, action: reset
Aug 22 22:40:24 epsilon kernel: [90525.601195] drm/i915: Resetting chip after gpu hang
Aug 22 22:40:26 epsilon kernel: [90527.599902] [drm] RC6 on
Aug 22 22:40:42 epsilon kernel: [90543.623173] [drm] stuck on render ring
Aug 22 22:40:42 epsilon kernel: [90543.623490] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [21887], reason: Engine(s) hung, action: reset
Aug 22 22:40:42 epsilon kernel: [90543.625282] drm/i915: Resetting chip after gpu hang
Aug 22 22:40:44 epsilon kernel: [90545.624000] [drm] RC6 on
Aug 22 22:41:06 epsilon kernel: [90567.611346] [drm] stuck on render ring
Aug 22 22:41:06 epsilon kernel: [90567.611448] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [21887], reason: Engine(s) hung, action: reset
Aug 22 22:41:06 epsilon kernel: [90567.612672] drm/i915: Resetting chip after gpu hang
Aug 22 22:41:08 epsilon kernel: [90569.612251] [drm] RC6 on
Aug 22 22:41:34 epsilon kernel: [90595.611658] [drm] stuck on render ring
Aug 22 22:41:34 epsilon kernel: [90595.611955] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [21887], reason: Engine(s) hung, action: reset
Aug 22 22:41:34 epsilon kernel: [90595.613772] drm/i915: Resetting chip after gpu hang
Aug 22 22:41:36 epsilon kernel: [90597.612433] [drm] RC6 on
Aug 22 22:41:56 epsilon kernel: [90617.623826] [drm] stuck on render ring
Aug 22 22:41:56 epsilon kernel: [90617.624120] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [21887], reason: Engine(s) hung, action: reset
Aug 22 22:41:56 epsilon kernel: [90617.625971] drm/i915: Resetting chip after gpu hang
Aug 22 22:41:58 epsilon kernel: [90619.612125] [drm] RC6 on
-----------------------------

How can that be? The Hang happens when switching from ido to regular
find-file. What has GPU to do with that?

-- Alex


Eli Zaretskii writes:

>> From: Alexander Asteroth <alexander.asteroth@h-brs.de>
>> Cc: Eli Zaretskii <eliz@gnu.org>, 28149@debbugs.gnu.org
>> Date: Tue, 22 Aug 2017 18:33:27 +0200
>> 
>> the source of error seems to be related to the graphics driver. Hangs
>> are related to these lines in syslog/dmesg:
>> 
>> --------------------
>> [63129.201509] [drm] stuck on render ring
>> [63129.201808] [drm] GPU HANG: ecode 9:0:0x84dffff8, in Xorg [8965], reason: Engine(s) hung, action: reset
>> [63129.203624] drm/i915: Resetting chip after gpu hang
>> [63131.202095] [drm] RC6 on
>> -------------------
>> 
>> which seem to be temporarly related to the error. Some Tickets about this
>> error are already open in freedesktop.org by other users. Let's hope
>> there will be a workaround.
>
> Thanks for letting us know.  I guess we can now close this bug, then?

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Eli Zaretskii]

> From: Alexander Asteroth <alexander.asteroth@h-brs.de>
> Cc: Alexander Asteroth <alexander.asteroth@h-brs.de>, 28149@debbugs.gnu.org
> Date: Tue, 22 Aug 2017 22:47:02 +0200
> 
> How can that be? The Hang happens when switching from ido to regular
> find-file. What has GPU to do with that?

I have no idea, sorry.

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Alexander Asteroth]

Dear all,

I migrated to Debian 9. Problem is completely solved.

Cheers,

        Alex

Eli Zaretskii writes:

>> From: Alexander Asteroth <alexander.asteroth@h-brs.de>
>> Cc: Alexander Asteroth <alexander.asteroth@h-brs.de>, 28149@debbugs.gnu.org
>> Date: Tue, 22 Aug 2017 22:47:02 +0200
>> 
>> How can that be? The Hang happens when switching from ido to regular
>> find-file. What has GPU to do with that?
>
> I have no idea, sorry.

bug#28149: 26.0.50; Emacs regularly hangs for multiple seconds in e.g. find-file

[Eli Zaretskii]

> From: Alexander Asteroth <alexander.asteroth@h-brs.de>
> Cc: Alexander Asteroth <alexander.asteroth@h-brs.de>, 28149@debbugs.gnu.org
> Date: Mon, 28 Aug 2017 12:59:29 +0200
> 
> I migrated to Debian 9. Problem is completely solved.

Thanks, closing.