Documentation

Learn how to use TrueAsync for building concurrent PHP applications.

Pool::idleCount

(PHP 8.6+, True Async 1.0)

public Pool::idleCount(): int

Returns the number of idle (unused) resources that are ready to be acquired.

Parameters

This method takes no parameters.

Return Value

The number of idle resources in the pool.

Examples

Example #1 Tracking idle resources

<?php

use Async\Pool;

$pool = new Pool(
    factory: fn() => new PDO('mysql:host=localhost;dbname=app', 'user', 'pass'),
    min: 3,
    max: 10
);

echo $pool->idleCount() . "\n"; // 3

$conn = $pool->acquire();
echo $pool->idleCount() . "\n"; // 2

$pool->release($conn);
echo $pool->idleCount() . "\n"; // 3

Example #2 Adaptive strategy

<?php

use Async\Pool;

$pool = new Pool(
    factory: fn() => createExpensiveResource(),
    min: 1,
    max: 20
);

// If few idle resources remain — reduce load
if ($pool->idleCount() < 2 && $pool->count() >= 18) {
    echo "Warning: pool is nearly exhausted\n";
}

See Also