redis-server window版

后端

6.81MB

16 需要积分: 1

立即下载

MSOpenTech’s Redis on Windows

We strive to have a stable, functionally equivalent and comparably performing version of Redis on

Windows. We have achieved performance nearly identical to the POSIX version running head-to-head

on identical hardware across the network. Aside from feature differences that help Redis take

advantage of the Windows infrastructure, our version of Redis should work in most situations with the

identical setup and configuration that one would use on a POSIX operating system.

How is Redis on Windows implemented?

Redis is a C code base that compiles under Visual Studio. Most of the code compiles with only minor

changes (due to syntactical differences between compilers and low-level API differences on Windows).

There are a few areas where there are significant differences in how efficient Windows programs

operate relative to POSIX programs. We have encapsulated most these differences in a platform specific

library. The areas where there are significant differences are:

• Networking APIs

• POSIX File Descriptors

• POSIX fork()

• Logging

• Windows Services API

Networking Differences

The Windows networking stack is split between user mode code and kernel mode code. Transitions

between user and kernel mode are expensive operations. The POSIX networking APIs on Windows

utilize a programming model that incurs significant performance loss due to the kernel/user mode

transitions. Efficient Windows networking code instead uses the IO Completion Port model to reduce

the impact of this behavior. The APIs used and the programming model for IO Completion is different

enough that we were forced to implement a new networking layer in Redis.

File Descriptors

In a POSIX operating system, all data sources (files, pipes, sockets, mail slots, etc.) are referenced in code

with a handle called a file descriptor. These are low value integers that increment by one with each

successive file descriptor creation. All POSIX APIs that work with file descriptors will function without the

programmer having to know what kind of data source a file descriptor represents. On Windows, each

kind of data source has a separate kind of HANDLE. APIs that work with one HANDLE type will not work

with another kind of HANDLE. In order to make Redis operate with its assumptions about file descriptor

values and data source agnosticism, we implemented a Redis File Descriptor API layer.

fork()

The POSIX version of Redis uses the fork() API. There is no equivalent in Windows, and it is an

exceedingly difficult API to completely simulate. For most of the uses of fork() we have used Windows

specific programming idioms to bypass the need to use a fork()-like API. The one case where we could

not do so was with the point-in-time heap snapshot behavior that the Redis persistence model is based

on. We tried several different approaches to work around the need for a fork()-like API, but always ran

into significant performance penalties and stability issues.

Redis-windows.zip 大约有19个文件