KnicKnic / WASM-ImageMagick

It seens that webworkers support transference of data betwee the worker and the page with a zero-copy operation, which results in a vast performance improvement when sending large data sets. We should use that to pass input and output files from and to the web-worker:

see call boundries

WASM-ImageMagick/src/magickApi.ts

Lines 59 to 70 in 9226e7c

    
           export function call(inputFiles: MagickInputFile[], command: string[]): Promise<CallResult> { 
        
             const request = { 
        
               files: inputFiles, 
        
               args: command, 
        
               requestNumber: magickWorkerPromisesKey, 
        
             } 
        
             const promise = CreatePromiseEvent() 
        
             magickWorkerPromises[magickWorkerPromisesKey] = promise 
        
             magickWorker.postMessage(request) 
        
             magickWorkerPromisesKey++ 
        
             return promise as Promise<CallResult> 
        
           }

WASM-ImageMagick/webworker.js

Lines 92 to 96 in 9226e7c

    
           message.outputFiles = responseFiles 
        
           message.stdout = stdout.map(s => s) 
        
           message.stderr = stderr.map(s => s) 
        
           message.exitCode = exitCode 
        
           postMessage(message)

WASM-ImageMagick/webworker.js

Lines 101 to 104 in 9226e7c

    
           onmessage = function (magickRequest) { 
        
             Module.messagesToProcess.push(magickRequest.data) 
        
             processFiles() 
        
           }

WASM-ImageMagick/src/magickApi.ts

Lines 139 to 150 in 9226e7c

    
           magickWorker.onmessage = e => { 
        
             const response = e.data 
        
             const promise = magickWorkerPromises[response.requestNumber] 
        
             delete magickWorkerPromises[response.requestNumber] 
        
             const result = { 
        
               outputFiles: response.outputFiles, 
        
               stdout: response.stdout, 
        
               stderr: response.stderr, 
        
               exitCode: response.exitCode || 0, 
        
             } 
        
             promise.resolve(result) 
        
           }

fixed

Hey @KnicKnic - did it improve performance ? (sorry to be just a spectator lately - promise will resume my work in the short term here since I have a couple of features in my branch and will need to use the library). Thanks!

@cancerberoSgx perf not really(copying a gig of ram doesn't use that much cpu(theoretically the max it could have saved in copying before would have only been .33GB saved twice(coming and going) for a total of .66GB) ). If I remember correctly there were scenarios with many files that it helped reduce the ram usage to such a point where it wouldn't exhaust the 1GB limit in chrome.

	export function call(inputFiles: MagickInputFile[], command: string[]): Promise<CallResult> {
	const request = {
	files: inputFiles,
	args: command,
	requestNumber: magickWorkerPromisesKey,
	}
	const promise = CreatePromiseEvent()
	magickWorkerPromises[magickWorkerPromisesKey] = promise
	magickWorker.postMessage(request)
	magickWorkerPromisesKey++
	return promise as Promise<CallResult>
	}

	message.outputFiles = responseFiles
	message.stdout = stdout.map(s => s)
	message.stderr = stderr.map(s => s)
	message.exitCode = exitCode
	postMessage(message)

	onmessage = function (magickRequest) {
	Module.messagesToProcess.push(magickRequest.data)
	processFiles()
	}

	magickWorker.onmessage = e => {
	const response = e.data
	const promise = magickWorkerPromises[response.requestNumber]
	delete magickWorkerPromises[response.requestNumber]
	const result = {
	outputFiles: response.outputFiles,
	stdout: response.stdout,
	stderr: response.stderr,
	exitCode: response.exitCode \|\| 0,
	}
	promise.resolve(result)
	}

Use Transferable objects to pass data between worker and page