Blktrace是linux系统下用来记录磁盘io读写请求的工具。它由两部分组成：一部分工作在内核态，现在已经是标准内核的一部分，它工作在块设备层；另一部分是用户态程序，由用户输入命令启动。-Blktrace is used to record under the linux system to read and write disk io request tool. It consists of two parts: the core part of state, is now a standard part of the kernel, it works in the block device layer　the other part is the user-state process, from user input command.