Cannot change the maximum number of file descriptors on squid

Issue

• We'd like to increase the maximum number of file descriptors on squid.

• The parameter max_filedescriptors in squid.conf doesn't work.

  # grep max_filedescriptors /etc/squid/squid.conf
  max_filedescriptors 4096
  
  # squidclient -l localhost -p 3128 mgr:info | grep descriptors
        Maximum number of file descriptors:   16384
        Available number of file descriptors: 16378
        Reserved number of file descriptors:   100