Maximum file handles allowed by OS

Linux can open 1024 files concurrently by each process by default:

 

http://m.blog.csdn.net/blog/keepersay/8593352

 

Windows can open 20000 files:

 

https://social.msdn.microsoft.com/Forums/windowsdesktop/en-US/ce6ce7df-b769-41b7-bccf-b75707c0a729/calculate-maximum-number-of-file-handles-at-run-time?forum=windowssdk