如果是ubuntu系统,光用ulimit -n没法改成最大值65535,只有修改文件/etc/security/limits.conf:
```shell
* hard nofile 65535
* soft nofile 65535
```
os x Yosemite
查看:
```shell
launchctl limit maxfiles
```
后两列是软件限制和硬件限制
要修改这个值需要创建两个文件/Library/LaunchDaemons/limit.maxfiles.plist和/Library/LaunchDaemons/limit.maxproc.plist文件:
limit.maxfiles.plist:
```shell
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
<string>limit.maxfiles</string>
<key>ProgramArguments</key>
<array>
<string>launchctl</string>
<string>limit</string>
<string>maxfiles</string>
<string>65536</string>
<string>65536</string>
</array>
<key>RunAtLoad</key>
<true/>
<key>ServiceIPC</key>
<false/>
</dict>
</plist>
```
limit.maxproc.plist:
```shell
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple/DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
<string>limit.maxproc</string>
<key>ProgramArguments</key>
<array>
<string>launchctl</string>
<string>limit</string>
<string>maxproc</string>
<string>2048</string>
<string>2048</string>
</array>
<key>RunAtLoad</key>
<true />
<key>ServiceIPC</key>
<false />
</dict>
</plist>
```
要确保两个文件的owner和group是root:wheel并且权限是-rw-r--r--的。
别忘了重启电脑。。