Number of threads running in a process

The following command gives a lot of information about the different processes running, including the number of threads in a process:

ps axo pid,ppid,rss,vsz,nlwp,cmd

Output columns:

• pid - Process ID
• ppid - Parent Process ID
• rss - Resident Set Size - physical memory
• vsz - Virtual Set Size - virtual memory
• nlwp - Number of Light Weight Processes - thread count
• cmd - Command

Source: http://serverfault.com/questions/138277/how-to-get-number-of-threads-per-process