Memory leak in Valetudo?

I discovered a small issue when using Home-Assistant to Poll the Map too often (every 10 seconds to get a sort of Live map). The /tmp directory filled and the vacuum locked up. A re-boot fixes the issue obviously.

I had done other things on the vacuum in the past so I might have had less space available than normal.

A quick work-around was to throw this into cron */1 * * * * cd /tmp/maps && ls -t /tmp/maps | tail -n +2 | xargs rm --

[Hypfer]

Testing Node 11.12 shows no signs of the leak so I guess https://github.com/nodejs/node/issues/23862 this is the culprit.

Fixed in Node 11.10 https://github.com/nodejs/node/pull/25993

[axel-kah]

Tracing the memory leak is a lot harder than I thought. Stumbling blocks:

Debugging on the robot:

• the binary output of pkg does not support the --inspect flag
• passing the --inspect flag to pkg --options does not work
• using memwatch-sigusr2 (depends on memwatch-next) requires crosscompilation (didn’t want to get into that)

Debugging on the host:

• usage of the VAC_MAP_TEST env variable was not self explanatory and could not find more documentation. What kind of file do you have to povide? I only found out it’s not a rendered png 😃
• Webserver.js needed slight adaptation to use custom paths for the rrlog files (copied from robot) and temp folder. This effectively mocked the robots filesystem and allows to use the regular code paths that create png maps from logfiles (win!).

Using --inspect was finally possible! Using chromiums debugger for stepping/breaking worked and taking heap snapshots as well. I took several snapshots while requesting 100 maps in between. Unfortunately comparing those snapshots is also not as straight forward as I thought. I can see that the heap increases and creates arrays almost linearly with request count but when trying to attribute it to object class names, function names or anything recognizable from the source I failed because It’s all just very generic names in the heap detail view.

Do the devs have any input for me how to debug this properly, what to look for?