Re: tramp "too many open files" [Re: bug#56606

[Michael Albinus <michael.albinus@gmx.de>]

Madhu <enometh@meer.net> writes:

Hi,

> The #56606 is archived and this may be unrelated and related to tramp,
> but I wanted to note I encoutered something similar on recent master
> (GNU Emacs 30.0.50 (build 2, x86_64-pc-linux-gnu, X toolkit, cairo
> version 1.16.0, Xaw3d scroll bars) of 2023-03-18) native compilation.

I might be wrong, but likely, bug#56606 is unrelated.

> Running the image after it compiled, when trying to save a zip file
> attachment in mew with y, I ran into the too many open files problem.
>
> ```
> $ lsof -n|wc -l
> 59510
> $ lsof -n |grep tramp|wc -l
> 4036
> ```
>
> most of the entries in lsof were
> ```
> COMMAND     PID   TID TASKCMD    USER   FD      TYPE             DEVICE    SIZE
> /OFF       NODE NAME
> emacs     30346 31097 gdbus     madhu  865r      REG               8,14       2
> 5318    1334064 /14/build/emacs/lisp/net/tramp-archive.elc
> emacs     30346 31097 gdbus     madhu  866r      REG               8,14       2
> 5318    1334064 /14/build/emacs/lisp/net/tramp-archive.elc
> emacs     30346 31097 gdbus     madhu  867r      REG               8,14       2
> 5318    1334064 /14/build/emacs/lisp/net/tramp-archive.elc
> emacs     30346 31097 gdbus     madhu  868r      REG               8,14       2
> ```

Hmm. tramp-archive.el uses th GVFS file system to read a file
archive. GVFS in this case uses libarchive(3).

> Of course I could do nothing but kill the process. I updated mew to 6.9
> and tried the sequence again in a fresh emacs, but wasn't able to
> reproduce this (but hit a vertico bug instead)
>
> If this looks familiar, or if someone has a clue about it, please tell
> me. Maybe I should a bug report under the `tramp' product if I hit it
> again.

What I could imagine is, that Emacs has many of the files open from the zip
file. However, mew shouldn't use tramp-archive.el ...

Well, I'm not familiar with mew. Could you please write a bug report,
which contains a recipe starting with "emacs -Q", and which tells how to
reach the point when the error appeared as reported above. The recipe is
also good when it doesn't show the error; I want to use it in order to
see how tramp-archive.el comes into play.

Best regards, Michael.