We use xwiki version 7.1.2 with tomcat 8 and nginx. In peak of load (when many users come in) we see that number of Threads grow and xwiki freeze. Ok, we increased maxThreads from 250 (default) up to 1100.
But it is not enough. We don't know cause of problem because number of simultaneous users in xwiki we have less than 300-400. We did threads dump and saw many url with words .../download/... as active thread (~ 800 of 1100 active threads ).
In our xwiki many pictures on pages (~10-15 per page) but we set
In xwiki attachement cache folder only 1700 files (i.e. xwiki.store.cache.capacity not need more).
What cause of problem with threads ? Why so many threads active long time ? And may be someone know good settings for tomcat ?