Linux Max threads limit and current thread count query

1, summary system limitations are:
/proc/sys/kernel/pid_max #查系统支持的最大线程数, usually very large, equivalent to the theoretical value

/proc/sys/kernel/threads-max

Max_user_process #系统限制某用户下最多可以运行多少进程或线程, using the command: ulimit-u

Note: Modify the value of the max_user_process, only need to modify the/etc/security/limits.conf, but this parameter needs to be modified/etc/security/limits.d/90-nproc.conf

Appendix:
Appendix 1:centos 6.* can be modified/etc/security/limits.d/90-nproc.conf
My side is by modifying/etc/security/limits.conf, adding at the end
* Soft Nproc 65535
* Hard Nproc 65535

View the default thread stack size, in bytes (Bytes), using the command: ulimit-s

/proc/sys/vm/max_map_count #硬件内存大小



2. The Java Virtual machine itself limits:
-xms #intial Java Heap Size
-xmx #maximum Java Heap Size
-XSS #the stack size for each thread


3. Query the current number of threads or processes of a program
# pstree-p ' ps-e | grep java | awk ' {print '} ' | Wc-l

It uses command substitution, about command substitution, which means that commands that are enclosed in "are prioritized, and then output as arguments to other commands.
Or
# Pstree-p Process Number | Wc-l

# TOP-HP Process Number | Wc-l

It's piped, about piping: pipe symbols, | Output from the left command as input to the right command


4. Query the current number of threads or processes used by the entire system
Pstree-p | Wc-l

Reprinted from: http://blog.csdn.net/wang7dao/article/details/16369381

Linux Max threads limit and current thread count query