Use pvm file for faster startup

[jeswr]

No description provided.

[josd]

The image is currently made with https://github.com/eyereasoner/eye/blob/master/install.sh line https://github.com/eyereasoner/eye/blob/master/install.sh#L34
The image is currently called in https://github.com/eyereasoner/eye/blob/master/eye.sh

[josd]

For the native eye the difference is

$ time swipl -f eye.pl -g main -- --version
eye --version
EYE v23.0105.0024 josd
SWI-Prolog version 9.1.2-17-gcd86f975e
starting 262 [msec cputime] 264 [msec walltime]

real    0m0.269s
user    0m0.261s
sys     0m0.011s

versus

$ time eye --version
eye --version
EYE v23.0105.0024 josd
SWI-Prolog version 9.1.2-17-gcd86f975e
starting 37 [msec cputime] 34 [msec walltime]

real    0m0.041s
user    0m0.040s
sys     0m0.002s

[jeswr]

What I am struggling with is trying to work out how to generate the .pvm file in the WASM version of SWIPL since those arguments are provided when you intialise the module. That is, at what point can I call Module.fs.writeFile('eye.pl', ...) in

import { SWIPLModule } from 'swipl-wasm/dist/common';
import { queryOnce, runQuery, SWIPL, writeEye } from '..';

(async () => {
  const Module : SWIPLModule= await SWIPL({ print: (s: string) => {
    console.log(s);
  }, arguments: ['-f', 'eye.pl', '-g', 'main', '--', '--version'] } as EmscriptenModule);

})();

[jeswr]

ignore this: it should just be swipl -x, I write this when I was tired and not looking closely at the sample files.

I've gotten as far as #21 - where we can now run npm i and the end result is that eye.pvm gets built and then we generate the file lib/eye.pvm.ts.

@josd The problem that I am now encountering is that I don't really know what do do with this; in the example you give you're calling eye --version from the command line without SWIPL being involved at all now - but with the WASM version we can't really do that as far as I can tell; so how would I run the pvm file using the current SWIPL WASM tooling?

// cc @rla as you had useful insight into the previous issue we encountered related to this.

[jeswr]

I've now tried

(async () => {
  const Module: SWIPLModule = await SWIPL({
    arguments: ['-x', './eye.pvm', '--', '"$@"'],
    preRun: (module: SWIPLModule) => {
      module.FS.writeFile('eye.pvm', fs.readFileSync(path.join(__dirname, '..', 'eye', 'eye.pvm')).toString());
    },
    print: console.log,
    printError: console.log
  });
})();

but it errors out with

[FATAL ERROR: at Fri Jan  6 10:51:30 2023
        Could not open resource database "./eye.pvm": Not a tty]
Aborted()

See #21 (comment) to reproduce locally

// cc @rla @JanWielemaker as it seems like it could be a problem with the swipl-wasm build rather than my usage of it

[JanWielemaker]

I don't know. Seems it cannot open eye.pvm and the reported errno is bogus.

[jeswr]

Seems it cannot open eye.pvm and the reported errno is bogus.

As in failing to parse it? It is definitely finding the file because if I remove the step adding eye.pvm we get the (sensible) error

[FATAL ERROR: at Sat Jan  7 17:23:34 2023
        Could not open resource database "eye.pvm": No such file or directory]
Aborted()

[JanWielemaker]

Ok. Note that the eye.pvm is a zip file. If it is opened but unusable as resource file it is probably an invalid zip file according to the embedded minizip library.

[jeswr]

Ah - thanks for clarifying (in particular the fact that it is a zip)! I've fixed it; the problem was doing a .toString() call that tried to interpreted it as utf8. @JanWielemaker @josd are you able to tell me what encoding is normally using in .pvm files? I've tried to google around but it seems .pvm is used for a few different things so it is hard to find the right answer.

[josd]

.pvm is a swipl quick load format which we use to make the generic reasoning engine eye.pvm but also and esp. for specialized reasoning engines preloaded with large amounts of so called static .ttl data and .n3 rules.

[josd]

Thank you so much @jeswr and @JanWielemaker, the eye initialization is now 5 times faster!