Quick Start

Quick Start

This page takes you from a working install to a useful measurement in under five minutes.

Step 1 — Mark two checkpoints

<?php

require __DIR__ . '/vendor/autoload.php';

use InitPHP\PerformanceMeter\PerformanceMeter;

PerformanceMeter::setPointer('start');

// the work you want to measure
usleep(50_000);

PerformanceMeter::setPointer('end');

setPointer($name) captures three things at the moment of the call:

• The current wall-clock time, via microtime(true)
• The emalloc-tracked memory usage, via memory_get_usage(false)
• The system-allocated memory usage, via memory_get_usage(true)

All three are stored in a single class-level registry, keyed by the lowercased name.

Step 2 — Ask for the delta

echo PerformanceMeter::elapsedTime('start', 'end'), " seconds\n";
echo PerformanceMeter::memoryUsage('start', 'end'),  " memory delta\n";

Output looks like:

0.0507 seconds
0.13KB memory delta

Step 3 — Skip the "end" checkpoint when you do not need it

elapsedTime() and memoryUsage() both default their second argument to null. When it is null, the current moment is captured and used as the end of the interval:

PerformanceMeter::setPointer('boot');

// ... whole script runs ...

echo PerformanceMeter::elapsedTime('boot'); // seconds since 'boot'

You only need an explicit end-checkpoint when you want to stop measuring before the script ends.

Step 4 — Use mark() if you prefer stopwatch vocabulary

mark($name) is a one-to-one alias of setPointer($name). Same state, same effect:

PerformanceMeter::mark('before');
heavy_work();
PerformanceMeter::mark('after');

echo PerformanceMeter::elapsedTime('before', 'after');

Step 5 — Be aware of the global registry

Every checkpoint lives in the same process-wide registry on the PerformanceMeter class. Two callers using the same name will overwrite each other:

PerformanceMeter::setPointer('x');
sleep(1);
PerformanceMeter::setPointer('x'); // overwrites — the first capture is gone

When you run independent measurements one after another (e.g. a benchmark loop comparing two implementations), call reset() between them:

foreach ($candidates as $name => $fn) {
    PerformanceMeter::reset();
    PerformanceMeter::setPointer('s');
    $fn();
    PerformanceMeter::setPointer('e');
    printf("%s: %ss\n", $name, PerformanceMeter::elapsedTime('s', 'e'));
}

Step 6 — Know when an unknown name throws

If you ask for a checkpoint that was never recorded, you get a PointerNotFoundException:

PerformanceMeter::elapsedTime('typo'); // throws PointerNotFoundException

This is deliberate — see Concepts → Fail-fast on unknown names for the reasoning. If you legitimately want a "measure if present" pattern, gate the call with has():

if (PerformanceMeter::has('boot')) {
    echo PerformanceMeter::elapsedTime('boot');
}

You now know enough

That is the entire model. The remaining wiki pages drill into specific cases:

• Concepts — the mental model in one page (recommended next read).
• API Reference — every method's parameters, return value, throws.
• Recipes — practical patterns: CLI benchmarks, cron timing, A/B comparison, peak memory tracking.
• Use Cases & Comparison — when this package is and is not the right tool.