prototype async API, with demonstrable perf improvements via benchmark

[cosmicexplorer]

This is another response to zip-rs/zip2#165.

After demonstrating an approach to parallelize extracting zip archives using rayon threadpools in #407, I wanted to further investigate whether introducing an async API might provide a more scalable approach to introducing parallelism (as I noted in https://github.com/zip-rs/zip/issues/403#issuecomment-1728747153). This PR prototypes such an API.

Example Usage

See the doctest: https://github.com/zip-rs/zip/blob/bc601d744bf8f61cb3eda88d39610de55098b120/src/read/tokio.rs#L554-L576

Performance & Benchmarking

cargo bench -- io demonstrates that this async implementation is faster to extract for large archives!

> cargo bench -- io
io/big archive(84642745 bytes)/<async copy_buf>
                        time:   [29.463 ms 29.661 ms 29.865 ms]
                        thrpt:  [2.6396 GiB/s 2.6577 GiB/s 2.6756 GiB/s]
io/big archive(84642745 bytes)/<async copy (no buf)>
                        time:   [72.790 ms 73.435 ms 74.127 ms]
                        thrpt:  [1.0634 GiB/s 1.0735 GiB/s 1.0830 GiB/s]
io/big archive(84642745 bytes)/<sync copy (no buf)>
                        time:   [35.737 ms 35.870 ms 36.016 ms]
                        thrpt:  [2.1887 GiB/s 2.1976 GiB/s 2.2058 GiB/s]
io/small archive(126517 bytes)/<async copy_buf>
                        time:   [113.44 µs 114.66 µs 115.86 µs]
                        thrpt:  [1.0170 GiB/s 1.0276 GiB/s 1.0386 GiB/s]
io/small archive(126517 bytes)/<async copy (no buf)>
                        time:   [167.58 µs 169.65 µs 171.53 µs]
                        thrpt:  [703.41 MiB/s 711.20 MiB/s 720.00 MiB/s]
io/small archive(126517 bytes)/<sync copy (no buf)>
                        time:   [60.929 µs 61.357 µs 61.835 µs]
                        thrpt:  [1.9055 GiB/s 1.9204 GiB/s 1.9339 GiB/s]
io/random archive(10106802 bytes)/<async copy_buf>
                        time:   [4.2838 ms 4.3385 ms 4.4067 ms]
                        thrpt:  [2.1360 GiB/s 2.1696 GiB/s 2.1973 GiB/s]
io/random archive(10106802 bytes)/<async copy (no buf)>
                        time:   [9.4273 ms 9.5448 ms 9.6646 ms]
                        thrpt:  [997.31 MiB/s 1009.8 MiB/s 1022.4 MiB/s]
io/random archive(10106802 bytes)/<sync copy (no buf)>
                        time:   [3.9525 ms 3.9812 ms 4.0152 ms]
                        thrpt:  [2.3443 GiB/s 2.3643 GiB/s 2.3814 GiB/s]
extract/big archive(84642745 bytes)/<async extraction>
                        time:   [779.27 ms 801.90 ms 824.78 ms]
                        thrpt:  [97.870 MiB/s 100.66 MiB/s 103.59 MiB/s]
extract/big archive(84642745 bytes)/<sync extraction>
                        time:   [802.74 ms 803.94 ms 805.23 ms]
                        thrpt:  [100.25 MiB/s 100.41 MiB/s 100.56 MiB/s]
extract/small archive(126517 bytes)/<async extraction>
                        time:   [9.5155 ms 9.5789 ms 9.6337 ms]
                        thrpt:  [12.524 MiB/s 12.596 MiB/s 12.680 MiB/s]
extract/small archive(126517 bytes)/<sync extraction>
                        time:   [2.3227 ms 2.3490 ms 2.3713 ms]
                        thrpt:  [50.881 MiB/s 51.365 MiB/s 51.946 MiB/s]
extract/random archive(10106802 bytes)/<async extraction>
                        time:   [160.18 ms 164.26 ms 169.09 ms]
                        thrpt:  [57.004 MiB/s 58.681 MiB/s 60.173 MiB/s]
extract/random archive(10106802 bytes)/<sync extraction>
                        time:   [37.677 ms 37.850 ms 38.045 ms]
                        thrpt:  [253.35 MiB/s 254.65 MiB/s 255.82 MiB/s]

Notably, this approach is already faster than the sync implementation, without even applying the optimizations requiring a cloneable file handle that were necessary in #407!

TODO

This is left as a draft because it adds a lot of extra dependencies, which I would like to avoid. It also directly depends on tokio, instead of using the async-executors crate to apply to any async executor. I'm going to spend some time to break out the extra code I had to write to make this async API work into a separate wrapper crate, which should allow this change to become much smaller and easier for maintainers to accept.

[Pr0methean]

Replaced with zip-rs/zip2#73.