PsyncLib

PsyncLib (net.nosial.psynclib) is a PHP library that introduces parallel operations into PHP without the need for additional software such as a Message Queue or a Job Queue. Using Shared Memory & Forking, PsyncLib allows you to create parallel operations by calling several simple functions.

Community

This project and many others from Nosial are available on multiple publicly available and free git repositories at

• n64
• GitHub
• Codeberg

Issues & Pull Requests are frequently checked and to be referenced accordingly in commits and changes, Nosial remains dedicated to keep these repositories up to date when possible.

For questions & discussions see the public Telegram community at @NosialDiscussions. We do encourage community support and discussions, please be respectful and follow the rules of the community.

Table of contents

• PsyncLib
  • Community
  • Table of contents
  • Versioning
  • Installation
  • Usage
  • Classes
    • P
    • Psync
      • public static function do(callable $callable, array $args = []): P
      • public static function isDone(P $p): bool
      • public static function waitFor(P $p): mixed
      • private static function close(P $p): void
      • public static function wait(): array
      • public static function total(): int
      • public static function running(): int
      • public static function clean(): int
      • public static function getSharedMemorySize(): int
      • public static function setSharedMemorySize(int $sharedMemorySize): void
      • public static function getSharedMemoryPermissions(): int
      • public static function setSharedMemoryPermissions(int $sharedMemoryPermissions): void
  • License
  • Contributing

Versioning

This library uses Semantic Versioning.

Installation

To install PsyncLib, you can use ncc. (can also be found at github) Run the following command:

ncc package install -p="nosial/libs.psync=latest@n64"

To add the package as a dependency to your project, add this entry under build{} -> dependencies[] in your project.json file:

{
  "name": "net.nosial.psynclib",
  "version": "latest",
  "source_type": "remote",
  "source": "nosial/libs.psync=latest@n64"
}

The GitHub alternative name is nosial/psynclib=latest@github if you prefer to use GitHub as the source.

Usage

Psync is called under the namespace \PsyncLib\Psync. The following is an example of how to use Psync to calculate the value of Pi using the Monte Carlo method in parallel using 4 processes, this will display the value of Pi and the time taken to calculate it per process and finally the total time in total the script took to run.

<?php
    // Require ncc, this is required to load the PsyncLib package
    require 'ncc';

    // Import the Psync package (Not needed if the project references the package as a dependency)
    import('net.nosial.psynclib');

    // Begin the fun
    $parentStart = microtime(true);

    $promises = [];
    for($i = 0; $i < 10; $i++) {
        $promises[] = \PsyncLib\Psync::do(function() {
            $start = microtime(true);
            $pi = 0;
            $n = 1000000;
            for($i = 1; $i < $n; $i++) {
                $pi += 4 * (pow(-1, $i + 1) / (2 * $i - 1));
            }
            $end = microtime(true);
            return ['result' => $pi, 'time' => $end - $start];
        });
    }

    // Wait for all promises to resolve
    /** @var \PsyncLib\P $p */
    foreach($promises as $p) {
        $result = \PsyncLib\Psync::waitFor($p);
        printf("Result: %f, Time: %f\n", $result['result'], $result['time']);
    }

    $parentEnd = microtime(true);
    printf("Parent Time: %f\n", $parentEnd - $parentStart);

Running this on a test machine, the output will be similar to the following:

Result: 3.141594, Time: 2.113697
Result: 3.141594, Time: 2.370120
Result: 3.141594, Time: 2.043246
Result: 3.141594, Time: 2.124459
Result: 3.141594, Time: 2.245291
Result: 3.141594, Time: 2.309868
Result: 3.141594, Time: 2.163053
Result: 3.141594, Time: 2.375659
Result: 3.141594, Time: 2.360129
Result: 3.141594, Time: 2.006329
Parent Time: 2.390980

Classes

Psync is a very lightweight library, it only has 2 classes:

P

The P class is a simple class that represents a promise, it is used to store the state of the promise, the object itself should be treated as a reference, it has contains no actual functionality.

• public function getUuid(): string - Returns the UUID of the promise
• public function getPid(): int - Returns the PID of the process
• public function getShm(): Shmop - Returns the Shared Memory object
• public function __toString(): string - Returns the UUID of the promise

Psync

The Psync class is the main class used to interact with the Psync Library

public static function do(callable $callable, array $args = []): P

This method creates a new promise by forking a process to execute the given callable function. The result of the callable is stored in shared memory and can be retrieved later.

• Parameters:

  • callable $callable: The function to be executed in the forked process.
  • array $args: An optional array of arguments to pass to the callable.

• Returns:

  • P: An instance of the P class representing the promise.

• Throws:

  • RuntimeException: If the shared memory segment or the process fork fails.

Usage Example:

<?php
    $p = \PsyncLib\Psync::do(function() {
        return 'Hello, World!';
    });

    // Wait for the promise to resolve
    $result = \PsyncLib\Psync::waitFor($p);
    echo $result; // Output: Hello, World!

public static function isDone(P $p): bool

This method checks if the given promise has completed its execution.

• Parameters:

  • P $p: The promise instance to check.

• Returns:

  • bool: true if the promise has completed, false otherwise.

• Throws:

  • RuntimeException: If there is an error while checking the process status.

Usage Example:

<?php
    $p = \PsyncLib\Psync::do(function() {
        return 'Hello, World!';
    });

    // Check if the promise has completed
    if (\PsyncLib\Psync::isDone($p)) {
        echo 'Promise is done!';
    } else {
        echo 'Promise is still running...';
    }

public static function waitFor(P $p): mixed

This method waits for the given promise to complete and retrieves the result stored in shared memory.

• Parameters:

  • P $p: The promise instance containing details about the process to wait for.

• Returns:

  • mixed: The result retrieved from the shared memory, which may throw an exception if an error occurred within the process.

• Throws:

  • Throwable: If the result is an exception, it will be thrown.

Usage Example:

<?php
    $p = \PsyncLib\Psync::do(function() {
        return 'Hello, World!';
    });

    // Wait for the promise to resolve
    $result = \PsyncLib\Psync::waitFor($p);
    echo $result; // Output: Hello, World!

private static function close(P $p): void

This method closes and cleans up resources associated with the given process.

• Parameters:

  • P $p: The process instance to be closed.

• Returns:

  • void

Usage Example:

<?php
    $p = \PsyncLib\Psync::do(function() {
        return 'Hello, World!';
    });

    // Close the process and clean up resources
    \PsyncLib\Psync::close($p);

public static function wait(): array

This method waits for the completion of all promises and returns their results.

• Returns:

  • array: An associative array containing the results of each promise, indexed by their unique identifiers (UUIDs).

• Throws:

  • Throwable: If any of the promises throw an exception, it will be thrown.

Usage Example:

<?php
    $promises = [];
    for($i = 0; $i < 10; $i++) {
        $promises[] = \PsyncLib\Psync::do(function() {
            return 'Hello, World!';
        });
    }

    // Wait for all promises to resolve
    $results = \PsyncLib\Psync::wait();
    foreach($results as $uuid => $result) {
        echo "UUID: $uuid, Result: $result\n";
    }

public static function total(): int

This method calculates the total number of promises.

• Returns:
  • int: The total number of promises.

Usage Example:

<?php
    $totalPromises = \PsyncLib\Psync::total();
    echo "Total Promises: $totalPromises\n";

public static function running(): int

This method counts and returns the number of promises that are currently running.

• Returns:
  • int: The number of running promises.

Usage Example:

<?php
    $runningPromises = \PsyncLib\Psync::running();
    echo "Running Promises: $runningPromises\n";

public static function clean(): int

This method cleans up resources associated with promises that are not completed.

Iterates through a collection of promises, and for each promise that is not yet marked as done, calls a method to close and clean up the resource.

• Returns:
  • int: The number of promises that were closed and cleaned up.

Usage Example:

<?php
    $cleanedPromises = \PsyncLib\Psync::clean();
    echo "Cleaned Promises: $cleanedPromises\n";

public static function getSharedMemorySize(): int

This method returns the size of the shared memory.

• Returns:
  • int: The size of the shared memory.

Usage Example:

<?php
    $sharedMemorySize = \PsyncLib\Psync::getSharedMemorySize();
    echo "Shared Memory Size: $sharedMemorySize\n";

public static function setSharedMemorySize(int $sharedMemorySize): void

This method sets the size of the shared memory.

• Parameters:

  • int $sharedMemorySize: The new size for the shared memory.

• Returns:

  • void

Usage Example:

<?php
    \PsyncLib\Psync::setSharedMemorySize(1024);
    echo "Shared Memory Size set to 1024\n";

public static function getSharedMemoryPermissions(): int

This method returns the permissions of the shared memory.

• Returns:
  • int: The permissions of the shared memory.

Usage Example:

<?php
    $sharedMemoryPermissions = \PsyncLib\Psync::getSharedMemoryPermissions();
    echo "Shared Memory Permissions: $sharedMemoryPermissions\n";

public static function setSharedMemoryPermissions(int $sharedMemoryPermissions): void

This method sets the permissions for the shared memory.

• Parameters:

  • int $sharedMemoryPermissions: The permissions to be set for the shared memory.

• Returns:

  • void

Usage Example:

<?php
    \PsyncLib\Psync::setSharedMemoryPermissions(0666);
    echo "Shared Memory Permissions set to 0666\n";

License

This project is licensed under the MIT License - see the LICENSE file for details

Contributing

Feel free to contribute to this project by submitting a pull request or opening an issue.