Cache init params

[aguycalled]

Is there any possibility to cache the params generated on Init() or any drawdown from doing so?

iOS' JavaScriptCore does not support WASM, so I'm being forced to build mcl-wasm with WASM=0 in order to be able to use it in a React Native app, but the initialisation time is too slow (other operations execute with an acceptable speed). Thinking that hardcoding the values could help speeding up boot time.

Thanks!

[herumi]

What parameters do you want to increase the speed of? If it is BLS12_381, then I think that some pre-computed values can be embedded.

[aguycalled]

Yes it would be BLS12-381. Could you provide me some guidance on how to do it? Thx

[herumi]

How can I build mcl without wasm and check it? On Linux, I modified mcl-wasm/Makefile and tested it.

-EMCC_OPT+=-s WASM=1 -s NO_EXIT_RUNTIME=1 -s NODEJS_CATCH_EXIT=0 -s NODEJS_CATCH_REJECTION=0
+EMCC_OPT+=-s WASM=0 -s NO_EXIT_RUNTIME=1 -s NODEJS_CATCH_EXIT=0 -s NODEJS_CATCH_REJECTION=0

>cat t.js
'use strict'
const mcl = require('./dist/index.js')
const assert = require('assert')
const { performance } = require('perf_hooks')

const curveTest = (curveType, name) => {
  const start = performance.now()
  mcl.init(curveType)
    .then(() => {
      try {
        const end = performance.now()
        console.log('time=' + (end - start))
      } catch (e) {
        console.log(`TEST FAIL ${e}`)
        assert(false)
      }
    })
}

curveTest(mcl.BLS12_381)

>node t.js
time=89.65

It does not look so slow.

[aguycalled]

Yes, that's the way I build it too.

On a iOS device with a React Native app, await mcl.init(mcl.BLS12_381) takes around 1 minute. The iOS simulator runs fast, so it must be something specific to running on iOS.

[herumi]

await mcl.init(mcl.BLS12_381) takes around 1 minute.

Can you profile which functions are slow?

[aguycalled]

I will try to do it, but not sure what's the right way to profile C++ code compiled as JavaScript (no WASM) running on an iOS device.

[aguycalled]

I've been able to look into this with more detail and the real cause of the slowness are some later calls to deserializeHexStrToG1, which takes 60ms each time, and not mcl.init.

[herumi]

May I close this issue because the reason for the slow initialization is not mcl.init?