potiuk opened a new pull request, #58944:
URL: https://github.com/apache/airflow/pull/58944

   With .pyc files removal after compilation we save very little space. 
Uncompressed sizes of regular airflow image are:
   
   Before  7.63GB
   After   7.66GB
   
   So we have images bigger by < 0.5%
   
   And it seems that long running containers without those files can suffer 
from continuous attempts to recreate the .pyc files that fail due to lack of 
permissions and cause negative dentries to be continuously created:
   
   https://lwn.net/Articles/814535/
   
   Those negative dentries are created by kernel - caching the fact that a file 
was not available - which speeds up lookup but also takes a bit of memory. It 
seems that when compiled Python has the .pyc files removed, it tries to 
recreate them with timestamped entries every time new interpreter is started.
   
   While this is not a problem for long running processes - because those 
interpreters are run exactly once per container, this is a problem if you use 
`exec` in containers to run Health Checks.
   
   Evey health-check creates a new interpreter and every time it is created, a 
new negative dentries to take kernel memory.
   
   By not removing the .pyc files we increase a bit the size of the image but 
improve a little the startup time (no need to compile Python internal .py 
files, as well as get rid of the negative dentries problem.
   
   This PR likely:
   
   Fixes: #58509
   Fixes: #42195
   
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