Unfortunately, `--enable-mutex-timing` is a leftover option that now does nothing. One option is to enable logging – following this guide https://wiki.mpich.org/mpich/index.php/Debug_Event_Logging . If you set `MPICH_DBG_CLASS=THREAD`, you should see in the log file entries like “enter/exit MPIDU_Thread_mutex_lock xxx”, with timestamps. If that is insufficient for you, you may have manually insert your own timing harness. The file you should modify is `src/mpid/common/thread/mpidu_thread_fallback.h`. Hope that helps. -- Hui Zhou From: Yongyu Chen via discuss <[email protected]> Date: Wednesday, March 17, 2021 at 2:39 PM To: [email protected] <[email protected]> Cc: Yongyu Chen <[email protected]> Subject: [mpich-discuss] A question about mutex timing Dear sir or madam, I enabled a feature on configuring the mpi library, which is --enable-mutex-timing (calculate the time spent waiting on mutexes). But I don’t know how to use it. Could you provide me with some ideas or solutions? Thank you for reading, I appreciate your replies! Sincerely, Yongyu Chen Sincerely, Yongyu Chen