Additional information. Concurrent_connection is update in increment_count_by_name ([client|user]_stats) and increment_count_by_id (thread_stats).
Before fix this information updated just after thread complete (and just for this thread), as result Concurrent_connection always zero.
After my fix, set_connection_stats clean all Concurrent_connections counter, and calculate it directly from every thread (set_connection_stats called on SHOW [CLIENT|THREAD|USER]_STATS).
Additional information. Concurrent_ connection is update in increment_ count_by_ name ([client| user]_stats) and increment_ count_by_ id (thread_stats).
Before fix this information updated just after thread complete (and just for this thread), as result Concurrent_ connection always zero.
After my fix, set_connection_ stats clean all Concurrent_ connections counter, and calculate it directly from every thread (set_connection _stats called on SHOW [CLIENT| THREAD| USER]_STATS) .