FreeBSD 11.0-BETA4 发布了，FreeBSD是一种自由类Unix操作系统，是由经过BSD、386BSD和4.4BSD发展而来的类Unix的一个重要分支。

本次发布主要改进记录如下：

• The mtx_trylock_spin(9) kernel synchronization primitive was added.
  

• The machdep.disable_msix_migration loader tunable has been re-enabled
    for EC2 AMIs.
  

• The iwm(4) and iwmfw(4) drivers have been updated.
  

• The new system hardening options have been fixed to avoid overwriting
  

• ther options selected during install time.
  

• Several build-related fixes.
  

• Several miscellaneous bug fixes.

下载地址：ftp://ftp.freebsd.org/pub/FreeBSD/releases/ISO-IMAGES/11.0/