Beat names longer than 16 characters break the process stats reporting

[eirc]

For confirmed bugs, please report:

• Version: 7.3.1
• Operating System: Linux
• Steps to Reproduce: Create a new beat with a name longer than 16 characters, run it. You'll get errors like:

DEBUG   [processes]     process/process.go:480  Process name does not matches the provided regex; pid=XXX; name=<ONLY THE FIRST 16 LETTERS OF THE BEAT NAME>: <nil>
ERROR   instance/metrics.go:92  Error while getting memory usage: error retrieving process stats: cannot find matching process for pid=XXX

The problem is in libbeat/metric/system/process/process.go#L487 where a check is made to ensure it has the right process. It checks the name of the process against the name given by elastic/go-sysinfo. The later one is taken from /proc/<pid>/comm which only provides the first 16 bytes of a process name. (I'm not sure where the other process name is taken from, I think from gosigar? but I got a bit lost in there)

[elasticmachine]

Pinging @elastic/integrations-services (Team:Services)

[fearful-symmetry]

Fix here: #22550

[fearful-symmetry]

Fix has been merged, closing.