[web-devel] ANN: uhttpc - Minimal HTTP client library optimized for benchmarking

[Herbert Valerio Riedel]

Hello web-devel,

(sorry if you get this twice, I originally sent this from an
unsubscribed email address)

Even though I already announced this on reddit[1], I was reminded by one
of the comments this special-interest-group list exists, and therefore
I'd like to point your attention to

 http://hackage.haskell.org/package/uhttpc

which (as was pointed out by one reddit commenter) can be regarded as
the client-side of acme-http.


I've been able to get comparable measurements to what weighttp and ab
reports against HTTP servers such as nginx, but I've noticed some
sub-optimal results when using only a single kept-alive connection. For
instance, on my i7-3770 Linux desktop against an nginx server I get:

,----
| $ uhttpc-bench -n 200000 -t1 -c2 -k http://localhost/
| uhttpc-bench - a Haskell-based ab/weighttp-style webserver benchmarking tool
| 
| starting benchmark...
| finished in 15.024069 seconds, 200000 reqs (1 conns), 13312.0 req/s received
| status codes: 200000 HTTP-200
| data received: 11153.977 KiB/s, 171600000 bytes total (49200000 bytes http + 122400000 bytes content)
| rtt min/avg/max = 0.038/0.074/9.928 ms
`----

vs.

,----
| $ uhttpc-bench -n 200000 -t1 -c2 -k http://localhost/
| uhttpc-bench - a Haskell-based ab/weighttp-style webserver benchmarking tool
| 
| starting benchmark...
| finished in 4.849609 seconds, 200000 reqs (2 conns), 41240.4 req/s received
| status codes: 200000 HTTP-200
| data received: 34554.976 KiB/s, 171600000 bytes total (49200000 bytes http + 122400000 bytes content)
| rtt min/avg/max = 0.031/0.048/7.207 ms
`----

Whereas running `weighttp` with -c1 vs -c2 gives a linear 1x factor scaling of 20k
req/s vs 40k req/s (as opposed to the 1.5x factor scaling of
uhttpc-bench between -c1 and -c2)

Therefore, uhttpc-bench is significantly worse than weighttp when using only a
single connection. I can't explain that yet.


 [1]: http://www.reddit.com/r/haskell/comments/23yuvs/%C2%B5http_lowlevel_http_client_library_for/