[luatex] extreme slow down using pre release TL 2022 with lualatex

[Nasser M. Abbasi]

On 3/17/2022 2:52 PM, Patrick Gundlach wrote:
> Hello Nasser,
> 
> do you still have this issue?
> 

Yes.  It slows down as the file size increased.

lualatex is running. Not hanged or anything. But very slow.

PID USER  PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND
21615 me  20   0  832316 816708   6592 R  99.7  1.6 392:40.05 lualatex

The file has 9,000 problems (each on its own subsection, each problem
is read from separate latex file in separate sub folder).

When I had about 6,000 problems, it was fast. About 1-2 hrs to compile.

After adding more problems, I see the slow down.

I see the output going to the terminal OK as we speak. But it takes
about 20-30 seconds to see one line printed after the other on
the terminal. Very slow.

Initially the printed lines were coming to the screen
very fast (scrolling) but then the line scrolling becomes slower and slower.

At this rate it will take 10 months to compile this one file.

The Latex file does \subimport to load individual latex file for each
problem. There are almost 9,000 \subimport in the latex file.

When compiled to PDF it should be about 50,000 pdf pages.

I can make a zip file with everything and the command I use to compile
if someone wants to see for themselves. But it will be large zip.

I am running TL 2021 now. Same thing happened with TL 2022 pre.

May be because I am running this inside Ubuntu under windows 10
Linux subsystem this slow down happens. I do not know. I only have
one PC now. I need to go buy a new PC and install
Linux on it and try again to see if this is the cause.

Here is the current terminal output as we speak:

--------------------
Overfull \hbox (0.6622pt too wide) in paragraph at lines 600279--600280
[][]\TU/lmtt/m/n/12 dsolve(z*diff(diff(y(z),z),z)-2*diff(y(z),z)+z*y(z) = 0,y(z)
, singsol=all)
  []

[23658]
Underfull \hbox (badness 10000) in paragraph at lines 600317--600322

  []

(./OUTPUT/5819_Wednesday_January_12_2022_11_45_29_PM/index.tex
Overfull \hbox (16.01872pt too wide) in paragraph at lines 53--59
  []
  []

[23659

] [23660] [23661] [23662])
Overfull \hbox (2.0pt too wide) in paragraph at lines 600356--600356
[][][]
  []


Overfull \hbox (50.10214pt too wide) in paragraph at lines 600368--600369
[][]\TU/lmtt/m/n/12 dsolve
----------------------------------------

The time between each print out above takes about 20-30 seconds to show,
which is very long time.

> I run luajithbtex 1.12 (slightly different versions on different machines) without problems, but I do have problems with macOS arm64 1.15.
> 
> Sometimes the process runs fine, but most of the time it gets stuck using full CPU. I cannot reproduce this, this does not happen all the time.
> 
> Since I do have a very special setup, it is difficult to locate the error.
> 
> I still need to do some more testing with 1.15 on other machines (linux for example) to help any further tracking down of this issue.
> 
> This can be on my side, of course. I don't want to blame LuaTeX for this at all. All I can do is to state my observations.
> 
> Patrick
> 
> 

--Nasser