RPi5 with 8GB RAM - memory leak? sluggish performance after 2-3 weeks... swap usage... then fail.

[illigtr]

I originally built my indi-allsky using an RPi4-2GB with INDI lib-camera and a IMX477. I found that it would often start to swap memory and I'd have to reboot the device. This occurred even with RPI desktop disabled. I finally decided to just use a faster model with more RAM.

In general the RPi5 with 8 GB runs well, but after a few weeks, I start to get the alert that swap usage is over 5%. If I don't reboot soon, the entire system slows to a crawl.

If this a memory leak issue? How can one go about finding which program fails to release memory correctly?

As a stop gap solution, is there a way to reboot the server once a week to avoid this? I guess I could create a CRON job to stop indi services and just reboot,

Open to suggestions and discussion on this particular subject.

P.S.

I just rebooted, so my logs probably won't show anything interesting... but the next time my system go south with major swapping, then I'll try to post the logs and config.

[aaronwmorris]

There is nothing inherently bad about swap being used. The kernel basically decides what to swap and when. The tuning indi-allsky adds at the end of setup.sh can minimize swap, but the kernel handles this internally.

With 8GB of RAM, you could just disable swap entirely.

Set CONF_SWAPSIZE=0' in /etc/dphys-swapfile` and run

sudo sudo dphys-swapfile setup

[ldb20151]

Aaron,
You mentioned setup tuning -- is this the same tuning I'm prompted to have setup apply to my installation or upgrade, near the end of the setup process? If so, I always answer 'no' to that prompt when upgrading because I thought it might make changes I didn't want to my config file. Now that its easier to backup the config, I guess it wouldn't be a huge risk, but I'm curious what your recommend a typical person doing an upgrade answer? Should I allow tuning to be applied as a rule? I have a 512MB swap size with my 8GB pi 5. I haven't noticed any problems.

-Larry

[aaronwmorris]

That is the setup tuning. The setup tuning only performs 2 changes:

• Kernel vm.swappiness = 1 to reduce the kernel's usage of swap. The default is 60.
• Set the systemd journal to be volatile so it is not writing to disk. This significantly reduces the disk I/O and reduces wear on MMC cards.

[illigtr]

@aaronwmorris Thanks for the tips, I'm just trying to track down why the system seems to run out of memory after a few weeks. I will disable swap per your suggestion and I'll monitor memory usage. If I see that the system starts to slow, then I'll collect the logs and post them. Thanks again.