Debugging advice

Debugging advice

[Adam Taylor]

My environment is (maybe unfortunately) Cygwin64 under Windows, of course.

Occasionally while working emacs stops responding to me and I watch it's
memory consumption rise from 407MB to 1533MB along with a ramp in CPU usage.

I want to find out what it is doing and can not find any information on how
to monitor background activity in Emacs.

Another clue is it doesn't seem to happen if Emacs is just quiescent: Just
up on the screen but I'm not actively using it. When using the editor, the
problem occurs on a relatively frequent beat rate - once every few minutes.
It takes out Emacs for about 20 seconds or so.

I've turned off anything on a time (like desktop-save-mode).

I'd love to figure out what Emacs runs off and does

Any pointers are greatly appreciated.

Thanks,
-Adam

Re: Debugging advice

[Eli Zaretskii]

> From: Adam Taylor <mr.adtaylor@gmail.com>
> Date: Fri, 16 Jun 2017 09:58:27 -0400
> 
> My environment is (maybe unfortunately) Cygwin64 under Windows, of course.
> 
> Occasionally while working emacs stops responding to me and I watch it's
> memory consumption rise from 407MB to 1533MB along with a ramp in CPU usage.
> 
> I want to find out what it is doing and can not find any information on how
> to monitor background activity in Emacs.
> 
> Another clue is it doesn't seem to happen if Emacs is just quiescent: Just
> up on the screen but I'm not actively using it. When using the editor, the
> problem occurs on a relatively frequent beat rate - once every few minutes.
> It takes out Emacs for about 20 seconds or so.
> 
> I've turned off anything on a time (like desktop-save-mode).
> 
> I'd love to figure out what Emacs runs off and does
> 
> Any pointers are greatly appreciated.

When Emacs freezes like that, attach a debugger and produce a C-level
backtrace.  Then report the backtrace together with any other relevant
details in a bug report created by "M-x report-emacs-bug RET" (in a
separate Emacs session, of course).  Send that to
bug-gnu-emacs@gnu.org.

Thanks.

Re: Debugging advice

[Stefan Monnier]

> My environment is (maybe unfortunately) Cygwin64 under Windows, of course.
> Occasionally while working emacs stops responding to me and I watch it's
> memory consumption rise from 407MB to 1533MB along with a ramp in CPU usage.
> I want to find out what it is doing and can not find any information on how
> to monitor background activity in Emacs.

A tool I've used for that in the past is the cpu profiler.  Try to
M-x profiler-start, then try and reproduce the problem and then M-x
profiler-report.


        Stefan

Re: Debugging advice

[Jude DaShiell]

I wonder, can something be put in a .emacs file so when emacs encounters 
an initialization error the first problem line number in the .emacs file 
would be stated automatically?

On Fri, 16 Jun 2017, Stefan Monnier wrote:

> Date: Fri, 16 Jun 2017 17:16:38
> From: Stefan Monnier <monnier@iro.umontreal.ca>
> To: help-gnu-emacs@gnu.org
> Subject: Re: Debugging advice
> 
>> My environment is (maybe unfortunately) Cygwin64 under Windows, of course.
>> Occasionally while working emacs stops responding to me and I watch it's
>> memory consumption rise from 407MB to 1533MB along with a ramp in CPU usage.
>> I want to find out what it is doing and can not find any information on how
>> to monitor background activity in Emacs.
>
> A tool I've used for that in the past is the cpu profiler.  Try to
> M-x profiler-start, then try and reproduce the problem and then M-x
> profiler-report.
>
>
>        Stefan
>
>
>

-- 

Re: Debugging advice

[Alexis]

Jude DaShiell <jdashiel@panix.com> writes:

> I wonder, can something be put in a .emacs file so when emacs
> encounters an initialization error the first problem line number 
> in
> the .emacs file would be stated automatically?

Not necessarily, as something like e.g. a failure to insert a 
closing
parenthesis might not cause an error until the ELisp reader 
reaches the
end of the file. (Yes, this has happened to me.)


Alexis.