github-actions[bot] opened a new pull request, #58947:
URL: https://github.com/apache/airflow/pull/58947

   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:
   (cherry picked from commit bcda5080b8f3b43c63f2b6e5abd788efe5d58582)
   
   Co-authored-by: Jarek Potiuk <[email protected]>
   Fixes: #58509
   Fixes: #42195


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