Re: info: memory exhausted for processing python3.10.info

[Gavin Smith]

On Mon, Oct 17, 2022 at 10:20:03PM +0200, Hilmar Preuße wrote:
> Dear maintainers,
> 
> info runs out of memory when trying to dump python3.10 docs on stdout:
> 
>    $ dpkg-query -W python3.10-doc
>    python3.10-doc    3.10.7-2
> 
>    $ info python3.10 > /dev/null
>    info: memory exhausted
> 
> This is for reproduction on a Debian unstable system. I used a 32bit system
> having 2GB physical RAM. During processing the RSS size raised to 1.8 GB.
> Yes, that info page is huge (4.5 MB compressed), nevertheless I would not
> expect such a huge mem utilization for processing. I could reproduce the
> issue using the latest git checkout.
> 
> Please be so kind to have a look at the issue.

I reproduced the issue.

I did not investigate fully why the memory usage was so high, but I've
committed a fix in commit f7e8f926d7.  info was searching for the Info
file for every single node (over 4500 of them) and I suspect that this
also led to memory allocation for the entire file each time. ( Neatly,
4500 * 4.5MB is about 2 GB.)

This use case is important for people who do

  info python3.10 | less