Root cause

Issues caused the problem:

• very long transactions on database entities,
• long processing of image extraction for posts that contains lot of chunks and images,
• infinite processing of some image urls that not provide an input stream,
• wrongly processed exceptions in post changed handler service.

Evaluation

2022/09/26 - No problem with acuiring new connections from database. Not connections that stay in 'idle in transaction' state forever. Application perfomance is back in normal state. All checks done.