pkgcache.bin.<random> files fill up drive

[Darren Conway]

Hello
This seems to be similar to bug 1050779.

This occurred on Ubuntu 12.04.5 LTS. apt-get version 0.8.16 compiled 8 Oct 2014.

I have a headless remote webcam server connected via the mobile telephone network. A new file pkgcache.bin.xxxyyy (where xxxyyy are random letters/numbers) is generated each day with the same time stamp (0625 am) and gets added to the /var/cache/apt/ dir. This continues until the entire root partition is full and the server locks up.

I understand that this should only happen if apt-get update is run but I don't do that. No one has access to run that command. I do not install any updates on the server once deployed. At present, the server has no connection to the internet, so these files are generated by the software on the server.

I receive a daily report emailed from the server. apt-get is not listed as a running process when the report is run at 0730.

What is worse is that this problem seems to have started itself. This server has been running since 2014 without issue. It has started to fill up the cache directory in the last 6 months for no obvious reasons. This has caused the server to lock up twice.

I am clearing the files with a daily a crontab job to run apt-get clean.

I checked the "apt" logs. There are no new entries from when initial installation was done.

I have asked for help here :
http://askubuntu.com/questions/873241/var-cache-apt-dir-filling-with-daily-pkgcache-bin-xxxyyy-files/873687#873687
without a response.

[Julian Andres Klode (juliank)]

This does not happen only with apt-get update. A new temporary file is created by (almost) every APT command if at least one of the main cache files is outdated. It is then renamed to the final file. If APT exits before the rename, the temporary filename might stay around until you run clean. Given that this only started 6 months ago, something must be trying to read information from the apt cache.

Given that we are talking about a 4 year old release that has its end of life in 3 months, I'm not going to spend any time investigating this. There have been a ton of changes in 4 years, and I do remember some cleanup in that area, and there have been no other reports about that AFAIK with recent releases.

That said, if you can find the cause and reproduce this in 16.04, we might be able to do something about it. But it's of course difficult: There will always be some temporary files remaining if APT crashes in the wrong moment. If you run a command and interrupt it with Ctrl+C, there will likely be a file laying around, and there is really nothing we can do about that.

[Darren Conway (darren-conway)]

Hi
Thanks for you prompt response. Given the age of the version I am running, I have low expectations around corrective action. I did read up bug reports where this issue was fixed prior to the release I have.

On a slightly wider issue, I have attempted to conduct troubleshooting on this problem. My "findings" include:

 - no known Linux application that will identify what process/program has created any given file.

 - I don't know of any marker that apt and related utilities might include in a file to identify the source utility.

 - I have looked at the /etc/apt/apt.conf/10Periodic file and turned on verbose "3" mode. No email was created when the cache file was created a 6:25am.

 - The MaxSize is set to "500" which is well under the capacity of the HD. Whichever program creates the cache files is ignoring the directory size limit.

 - The problem appears to have developed spontaneously without user intervention.

 - If there is a problem with a broken file, I don't know how to find it or fix it. Running "clean" gets rid of the cache files but doesn't stop them being created.

In short, troubleshooting apt problems seems to be more difficult that it should be. Perhaps this may be an area worth working on in future releases.

In the mean time, I will just set up a daily cron "clean" job to clear the cache. I don't expect any action or further discussion.

Cheers

Dazz

[Darren Conway (darren-conway)]

Hello

In the /etc/apt/apt.conf.d/10periodic file I set:
APT::Periodic::Enable "0"
to disable update/upgrade script.

This stopped the generation of cache files.
Still nothing is recorded in the apt log files.

Dazz

[Launchpad Janitor (janitor)]

[Expired for apt (Ubuntu) because there has been no activity for 60 days.]