A simple script to update the nproc of the specified process

update_nproc.sh

#!/bin/bash

if [ $# -lt 1 ];then
    echo "usage:$0 pid [nproc=1024000]"
    exit 1
fi

pid=$1
if [ $# -ge 2 ];then
    nproc="$2ll"
else
    nproc="1024000ll"
fi

# 修改nproc
#Limit                     Soft Limit           Hard Limit           Units     
#Max cpu time              unlimited            unlimited            seconds   
#Max file size             unlimited            unlimited            bytes     
#Max data size             unlimited            unlimited            bytes     
#Max stack size            10485760             unlimited            bytes     
#Max core file size        unlimited            unlimited            bytes     
#Max resident set          unlimited            unlimited            bytes     
#Max processes             1024                 unlimited            processes 
#Max open files            65536                65536                files     
#Max locked memory         65536                65536                bytes     
#Max address space         unlimited            unlimited            bytes     
#Max file locks            unlimited            unlimited            locks     
#Max pending signals       256265               256265               signals   
#Max msgqueue size         819200               819200               bytes     
#Max nice priority         0                    0                    
#Max realtime priority     0                    0                    
#Max realtime timeout      unlimited            unlimited            us  

# setrlimit第一个参数为 `cat /proc/pid/limits` 后得到的列表中的偏移(从0开始)
gdb -p $pid << EOF >> nproc.log 2>&1
    set \$rlim = &{$nproc, $nproc} 
    p setrlimit(6, \$rlim)
    detach
    quit
EOF

# 查看是否修改成功
cat /proc/$pid/limits | grep "Max processes"