doc: add example of linking modules in a plugin

[chrisdickinson]

Add an example of dynamically linking plugins and a benchmark that does an apples-to-apples comparison of reflect using host functions vs. reflect using a linked wasm module. (To my surprise, the host functions are a little bit faster!)

reflect/reflect 65536 bytes
                        time:   [209.62 µs 210.25 µs 211.13 µs]
                        thrpt:  [296.03 MiB/s 297.27 MiB/s 298.16 MiB/s]
                 change:
                        time:   [-0.0996% +0.2021% +0.6613%] (p = 0.32 > 0.20)
                        thrpt:  [-0.6570% -0.2017% +0.0997%]
                        No change in performance detected.
reflect/reflect 655360 bytes
                        time:   [1.9814 ms 1.9839 ms 1.9865 ms]
                        thrpt:  [314.63 MiB/s 315.03 MiB/s 315.43 MiB/s]
                 change:
                        time:   [-0.0460% +0.1310% +0.3133%] (p = 0.15 < 0.20)
                        thrpt:  [-0.3123% -0.1308% +0.0460%]
                        Change within noise threshold.
reflect/reflect 6553600 bytes
                        time:   [20.818 ms 20.839 ms 20.860 ms]
                        thrpt:  [299.61 MiB/s 299.92 MiB/s 300.23 MiB/s]
                 change:
                        time:   [+0.5463% +0.6997% +0.8403%] (p = 0.00 < 0.20)
                        thrpt:  [-0.8333% -0.6949% -0.5434%]
                        Change within noise threshold.
reflect/reflect_linked 65536 bytes
                        time:   [231.47 µs 231.64 µs 231.82 µs]
                        thrpt:  [269.60 MiB/s 269.81 MiB/s 270.02 MiB/s]
                 change:
                        time:   [-0.0548% +0.0832% +0.2227%] (p = 0.24 > 0.20)
                        thrpt:  [-0.2222% -0.0831% +0.0548%]
                        No change in performance detected.
reflect/reflect_linked 655360 bytes
                        time:   [2.1875 ms 2.1889 ms 2.1903 ms]
                        thrpt:  [285.35 MiB/s 285.53 MiB/s 285.71 MiB/s]
                 change:
                        time:   [+0.8201% +0.9253% +1.0262%] (p = 0.00 < 0.20)
                        thrpt:  [-1.0157% -0.9168% -0.8135%]
                        Change within noise threshold.
reflect/reflect_linked 6553600 bytes
                        time:   [22.293 ms 22.310 ms 22.327 ms]
                        thrpt:  [279.93 MiB/s 280.14 MiB/s 280.35 MiB/s]
                 change:
                        time:   [+0.8597% +0.9710% +1.0857%] (p = 0.00 < 0.20)
                        thrpt:  [-1.0741% -0.9617% -0.8523%]
                        Change within noise threshold.

[bhelx]

We should talk about this as a team I think. I'm still a little confused as to how this will behave on different runtimes. And if it behaves differently, or doesn't work across all of them, we should be a little more cautious about people using it.

[bhelx]

This is okay to merge though, not a blocker!

[zshipko]

@bhelx I tested dynamic linking on the Rust-based SDKs and go-sdk - I think only js-sdk is missing support right now.

[chrisdickinson]

Thanks for the reviews! @zshipko excellent! I had read through the go-sdk code and found that the kernel was getting linked in, but wasn't 100% sure if other modules in the manifest would get linked in too – I was just about to test this.

I'm tracking JS support for linking here and hope to get it implemented and merged before 1.0.