Add LimitedStream benchmark

[carltongibson]

Hi @deepakdinesh1123 @smithdc1.

Have a look at the ticket here: https://code.djangoproject.com/ticket/33865

There's a proposal to optimise LimitedStream (which wraps the WSGI request body input stream to ensure we can't read into other requests...).

It might be nice to quickly add a benchmark for it, and then be able to say, "Look here's main, and here's the PR".
Are we there yet?

What do you think?

[deepakdinesh1123]

#58, in this PR I have added the benchmark based on the benchmarks (here)[https://code.djangoproject.com/attachment/ticket/33865/bench_limitedstream.py], and the results, were as follows

     before           after      ratio
 [e20e5d15]       [021916db]
 <main>           <pull/15872/head~3>
  115±3ms          125±2ms     1.09 
 other_benchmarks.limited_stream.benchmark.LimitedStreamBench.time_limited_stream_read
  116±1ms         132±20ms     1.14  
other_benchmarks.limited_stream.benchmark.LimitedStreamBench.time_limited_stream_read_8192
 82.1±3ms         95.0±9ms    ~1.16  
other_benchmarks.limited_stream.benchmark.LimitedStreamBench.time_limited_stream_readline
 89.1±5ms         89.2±7ms     1.00  
other_benchmarks.limited_stream.benchmark.LimitedStreamBench.time_limited_stream_readline_8192

At first, I had benchmarked all the methods together but I split them into separate methods, but still, the results mentioned in the (ticket)[https://code.djangoproject.com/ticket/33865#no1] differed from what I got, Are there any changes that I need to make to the benchmark?

[carltongibson]

Hey @ngnpope — Hoping this is of interest to you! 🙂

@deepakdinesh1123 is working to push forward the work @smithdc1 began to use ASV to regularly run benchmarks on Django.

Seeing your PR on LimitedStream, it looked like a good test case.

I don't know if there's enough info (README etc.) for you to have a proper investigation here yet... 😬 but I thought I'd give you a ping.

(@deepakdinesh1123 I have a bit of admin for next week to do this morning, then I'll sit down with this again. Thanks! 👍)

[ngnpope]

Thanks @carltongibson. I'm actually trying to start writing these benchmarks for optimisations with this effort in mind. Looking forward to seeing this realised 👏🏻