gin-limit
Stay under the limit with this handy Gin middleware.
Purpose
By default, http.ListenAndServe (which gin.Run wraps) will serve an unbounded number of requests. Limiting the number of simultaneous connections can sometimes greatly speed things up under load. Inspired by x/net/netutil.LimitListener.
Example
package main
import (
"github.com/aviddiviner/gin-limit"
"github.com/gin-gonic/gin"
)
func main() {
r := gin.Default()
r.Use(limit.MaxAllowed(20))
// ...
r.Run(":8080")
}Lies, damned lies and statistics
Everyone loves synthetic benchmarks, so have some numbers from my 2015 Macbook (on a fast rendering page; single sqlite query, basic templates).
% wrk -t12 -c400 -d20s http://localhost:4560/
Running 20s test @ http://localhost:4560/
12 threads and 400 connections
Thread Stats Avg Stdev Max +/- Stdev
Latency 848.63ms 525.39ms 1.64s 62.81%
Req/Sec 45.43 61.85 360.00 90.50%
8908 requests in 20.10s, 21.91MB read
Socket errors: connect 0, read 219, write 0, timeout 0
Requests/sec: 443.19
Transfer/sec: 1.09MB
Now 10x faster with limit.MaxAllowed(3) (although that would be higher in the real world). Hooray!
% wrk -t12 -c400 -d20s http://localhost:4560/
Running 20s test @ http://localhost:4560/
12 threads and 400 connections
Thread Stats Avg Stdev Max +/- Stdev
Latency 94.40ms 32.65ms 656.72ms 86.44%
Req/Sec 351.61 84.32 666.00 79.32%
84181 requests in 20.09s, 207.05MB read
Socket errors: connect 0, read 165, write 0, timeout 0
Requests/sec: 4189.75
Transfer/sec: 10.30MB