guard

Guard

guard is a generic high performance circuit breaker & proxy written in Go. It has four major components:

• radix tree & response status ring: which stores registered URLs
• load balancer: which distributes requests(algorithms: randomized distribute, round robin, weighted round robin)
• circuit breaker: which makes sure your backend services will not be broken down by a large quantity of requests
• proxy server: it's based on fasthttp

Workflow

Benchmark

I've made a simple benchmark on my laptop(i5-3210M CPU @ 2.50GHz with 4 cores):

…

For now, guard's proxy performance is about 55% of Nginx 1.76x faster than Nginx, and I'm still working on it! Don't worry, it will become better and better!

By the way, thanks the suggestion from @dongzerun, by configure the GOGC in environment, guard's proxy performance is about 70% of Nginx. guard does not allocate much memory now, GOGC does not make a change, but still say thanks to @dongzerun!

TODO

moved to https://github.com/jiajunhuang/guard/projects/1

Set it up

1. build it using go get -u:

$ go get -u github.com/jiajunhuang/guard

1. start it

$ guard

1. now you need to register an application by send a POST request to http://127.0.0.1:12345/app with json like this:

{
    "name": "www.example.com",
    "backends": ["127.0.0.1:80", "127.0.0.1:80", "127.0.0.1:80"],
    "weights": [5, 1, 1],
    "ratio": 0.3,
    "paths": ["/"],
    "methods": ["GET"],
    "fallback_type": "text",
    "fallback_content": "hello world"
}

I'm doing it like this:

$ http POST :12345/app < backends.json 
HTTP/1.1 200 OK
Content-Length: 8
Content-Type: text/plain; charset=utf-8
Date: Sun, 21 Jan 2018 08:51:16 GMT

success!

1. and now, it works! whoops! try it:

$ http :23456 'Host: www.example.com'
HTTP/1.1 200 OK
...

1. by the way, you can inspect your configuration by visit http://127.0.0.1:12345/ :

…

Changelogs

• 2018-01-25: rewrite proxy from net/http to fasthttp, it's super fast now!
• 2018-01-24: rewrite radix tree & statistics module, it's lock-free now!
• 2018-01-22: add randomized distribute, naive round robin algorithms
• 2018-01-21: rewrite status statistics module
• 2018-01-20: guard works!
• 2018-01-19: first commit

Thanks

• Golang
• fasthttp
• httprouter