/**
* Start production profiling for the application.
*
* There are three modes for profiling:
*
* 1. Wall-time only profiling of the complete request (no overhead)
* 2. Full profile/trace using xhprof (depending of # function calls
* significant overhead)
* 3. Whitelist-profiling mode only interesting functions.
* (5-40% overhead, requires custom xhprof version >= 0.95)
*
* Decisions to profile are made based on a sample-rate and random picks.
* You can influence the sample rate and pick a value that suites your
* application. Applications with lower request rates need a much higher
* transaction rate (25-50%) than applications with high load (<= 1%).
*
* Factors that influence sample rate:
*
* 1. Second parameter $sampleRate to start() method.
* 2. _qprofiler Query Parameter (string key is deprecated or array)
* 3. Cookie TIDEWAYS_SESSION
* 4. TIDEWAYS_SAMPLERATE environment variable.
*
* start() automatically invokes a register shutdown handler that stops and
* transmits the profiling data to the local daemon for further processing.
*
* @param array|string $options Either options array or api key (when string)
* @param int $sampleRate Deprecated, use "sample_rate" key in options instead.
*
* @return void
*/
public static function start($options = array(), $sampleRate = null)
{
if (self::$mode !== self::MODE_NONE) {
return;
}
if (!is_array($options)) {
$options = array('api_key' => $options);
}
if ($sampleRate !== null) {
$options['sample_rate'] = $sampleRate;
}
$defaults = array('api_key' => isset($_SERVER['TIDEWAYS_APIKEY']) ? $_SERVER['TIDEWAYS_APIKEY'] : ini_get("tideways.api_key"), 'sample_rate' => isset($_SERVER['TIDEWAYS_SAMPLERATE']) ? intval($_SERVER['TIDEWAYS_SAMPLERATE']) : ini_get("tideways.sample_rate"), 'collect' => isset($_SERVER['TIDEWAYS_COLLECT']) ? $_SERVER['TIDEWAYS_COLLECT'] : (ini_get("tideways.collect") ?: self::MODE_TRACING), 'monitor' => isset($_SERVER['TIDEWAYS_MONITOR']) ? $_SERVER['TIDEWAYS_MONITOR'] : (ini_get("tideways.monitor") ?: self::MODE_BASIC), 'distributed_tracing_hosts' => isset($_SERVER['TIDEWAYS_ALLOWED_HOSTS']) ? $_SERVER['TIDEWAYS_ALLOWED_HOSTS'] : (ini_get("tideways.distributed_tracing_hosts") ?: '127.0.0.1'), 'distributed_trace' => null);
$options = array_merge($defaults, $options);
if (strlen((string) $options['api_key']) === 0) {
return;
}
self::init($options['api_key'], $options['distributed_trace'], $options['distributed_tracing_hosts']);
self::$mode = self::decideProfiling($options['sample_rate'], $options);
if (self::$extension === self::EXTENSION_TIDEWAYS) {
switch (self::$mode) {
case self::MODE_FULL:
$flags = 0;
break;
case self::MODE_PROFILING:
$flags = TIDEWAYS_FLAGS_NO_SPANS;
break;
case self::MODE_TRACING:
$flags = TIDEWAYS_FLAGS_NO_HIERACHICAL;
break;
default:
$flags = TIDEWAYS_FLAGS_NO_COMPILE | TIDEWAYS_FLAGS_NO_USERLAND | TIDEWAYS_FLAGS_NO_BUILTINS;
break;
}
self::$currentRootSpan = new \Tideways\Traces\TwExtensionSpan(0);
tideways_enable($flags, self::$defaultOptions);
if (($flags & TIDEWAYS_FLAGS_NO_SPANS) === 0) {
foreach (self::$defaultOptions['watches'] as $watch => $category) {
tideways_span_watch($watch, $category);
}
foreach (self::$defaultOptions['callbacks'] as $function => $callback) {
tideways_span_callback($function, $callback);
}
}
} elseif (self::$extension === self::EXTENSION_XHPROF && (self::$mode & self::MODE_PROFILING) > 0) {
\Tideways\Traces\PhpSpan::clear();
self::$currentRootSpan = new \Tideways\Traces\PhpSpan(0, 'app');
self::$currentRootSpan->startTimer();
xhprof_enable(0, self::$defaultOptions);
} else {
\Tideways\Traces\PhpSpan::clear();
self::$currentRootSpan = new \Tideways\Traces\PhpSpan(0, 'app');
self::$currentRootSpan->startTimer();
}
}
/**
* Enable the profiler in the given $mode.
*
* @param string $mode
* @return void
*/
private static function enableProfiler($mode)
{
self::$mode = $mode;
if (self::$extension === self::EXTENSION_TIDEWAYS && self::$mode !== self::MODE_NONE) {
switch (self::$mode) {
case self::MODE_FULL:
$flags = 0;
break;
case self::MODE_PROFILING:
$flags = TIDEWAYS_FLAGS_NO_SPANS;
break;
case self::MODE_TRACING:
$flags = TIDEWAYS_FLAGS_NO_HIERACHICAL;
break;
default:
$flags = TIDEWAYS_FLAGS_NO_COMPILE | TIDEWAYS_FLAGS_NO_USERLAND | TIDEWAYS_FLAGS_NO_BUILTINS;
break;
}
self::$currentRootSpan = new \Tideways\Traces\TwExtensionSpan(0);
tideways_enable($flags, self::$defaultOptions);
if (($flags & TIDEWAYS_FLAGS_NO_SPANS) === 0) {
foreach (self::$defaultOptions['watches'] as $watch => $category) {
tideways_span_watch($watch, $category);
}
foreach (self::$defaultOptions['callbacks'] as $function => $callback) {
tideways_span_callback($function, $callback);
}
}
self::log(2, "Starting tideways extension for " . self::$trace['apiKey'] . " with mode: " . $mode);
} elseif (self::$extension === self::EXTENSION_XHPROF && (self::$mode & self::MODE_PROFILING) > 0) {
\Tideways\Traces\PhpSpan::clear();
self::$currentRootSpan = new \Tideways\Traces\PhpSpan(0, 'app');
self::$currentRootSpan->startTimer();
xhprof_enable(0, self::$defaultOptions);
self::log(2, "Starting xhprof extension for " . self::$trace['apiKey'] . " with mode: " . $mode);
} else {
\Tideways\Traces\PhpSpan::clear();
self::$currentRootSpan = new \Tideways\Traces\PhpSpan(0, 'app');
self::$currentRootSpan->startTimer();
self::log(2, "Starting non-extension based tracing for " . self::$trace['apiKey'] . " with mode: " . $mode);
}
}
