Re: Question about bignum usage

[Gerd Möllmann]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Gerd Möllmann <gerd.moellmann@gmail.com>
>> Date: Thu, 20 Jun 2024 07:59:36 +0200
>> 
>> In the igc branch, I see that Emacs creates bigints in an rate that I
>> find astonishsing, thousands in a few minutes. Most backtraces look like
>> this.
>> 
>>   * frame #0: 0x00000001000f9ce8 emacs`make_integer_mpz [inlined] 
>> make_bignum_bits(bits=71) at bignum.c:99:7 [opt]
>>     frame #1: 0x00000001000f9ce8 emacs`make_integer_mpz at bignum.c:170:10 
>> [opt]
>>     frame #2: 0x00000001001beb48 
>> emacs`decode_time_components(form=TIMEFORM_HI_LO_US_PS, high=<unavailable>, 
>> low=<unavailable>, usec=<unavailable>, psec=<unavailable>, 
>> result=0x000000016fdfde50, dresult=0x0000000000000000) at timefns.c:812:27 
>> [opt]
>>     frame #3: 0x00000001001be7e4 emacs`list4_to_timespec(high=<unavailable>, 
>> low=<unavailable>, usec=<unavailable>, psec=<unavailable>, 
>> result=0x000000016fdfdec0) at timefns.c:1008:7 [opt]
>>     frame #4: 0x00000001000e1c98 emacs`timer_check [inlined] 
>> decode_timer(timer=(struct Lisp_Vector *) $2 = 0x000000010ab42538, 
>> result=0x000000016fdfdec0) at keyboard.c:4648:10 [opt]
>>     frame #5: 0x00000001000e1c54 emacs`timer_check at keyboard.c:4713:10 
>> [opt]
>>     frame #6: 0x00000001000e1b44 emacs`timer_check at keyboard.c:4856:18 
>> [opt]
>>     frame #7: 0x00000001000df51c emacs`detect_input_pending_run_timers 
>> [inlined] readable_events(flags=1) at keyboard.c:3577:5 [opt]
>>     frame #8: 0x00000001000df518 emacs`detect_input_pending_run_timers 
>> [inlined] get_input_pending(flags=1) at keyboard.c:7859:42 [opt]
>>     frame #9: 0x00000001000df508 
>> emacs`detect_input_pending_run_timers(do_display=true) at keyboard.c:11563:5 
>> [opt]
>> 
>> Is this expected?
>
> Why not?  Time values are known to produce bignums, yes.  

Ok.

> What does list-timers show on that system?

               1.0s         5.0s auto-revert-buffers
               5.4s            - undo-auto--boundary-timer
           4m 19.0s           5m persistent-scratch-save
   *           0.1s            t show-paren-function
   *           0.5s            t posframe-hidehandler-daemon-function
   *           0.5s            t #f(compiled-function () #<bytecode 
-0x181a979fe3c9ba30> [jit-lock--antiblink-grace-timer jit-lock-context-fontify])
   *           0.5s      :repeat blink-cursor-start
   *           1.0s            t which-key--update