Merge 'minor-next' into 'major-next'

Automatic merge performed by: https://github.com/pmmp/RestrictedActions/actions/runs/12344337356

resources/pocketmine.yml

@@ -54,12 +54,6 @@ memory:
     #This only affects the main thread. Other threads should fire their own collections
     period: 36000
 
-    #Fire asynchronous tasks to collect garbage from workers
-    collect-async-worker: true
-
-    #Trigger on low memory
-    low-memory-trigger: true
-
   #Settings controlling memory dump handling.
   memory-dump:
     #Dump memory from async workers as well as the main thread. If you have issues with segfaults when dumping memory, disable this setting.
@@ -69,16 +63,6 @@ memory:
     #Cap maximum render distance per player when low memory is triggered. Set to 0 to disable cap.
     chunk-radius: 4
 
-    #Do chunk garbage collection on trigger
-    trigger-chunk-collect: true
-
-  world-caches:
-    #Disallow adding to world chunk-packet caches when memory is low
-    disable-chunk-cache: true
-    #Clear world caches when memory is low
-    low-memory-trigger: true
-
-
 network:
   #Threshold for batching packets, in bytes. Only these packets will be compressed
   #Set to 0 to compress everything, -1 to disable.

src/GarbageCollectorManager.php

@@ -0,0 +1,103 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ *
+ *
+ */
+
+declare(strict_types=1);
+
+namespace pocketmine;
+
+use pocketmine\timings\TimingsHandler;
+use function gc_collect_cycles;
+use function gc_disable;
+use function gc_status;
+use function hrtime;
+use function max;
+use function min;
+use function number_format;
+
+/**
+ * Allows threads to manually trigger the cyclic garbage collector using a threshold like PHP's own garbage collector,
+ * but triggered at a time that suits the thread instead of in random code pathways.
+ *
+ * The GC trigger behaviour in this class was adapted from Zend/zend_gc.c as of PHP 8.3.14.
+ */
+final class GarbageCollectorManager{
+	//TODO: These values could be adjusted to better suit PM, but for now we just want to mirror PHP GC to minimize
+	//behavioural changes.
+	private const GC_THRESHOLD_TRIGGER = 100;
+	private const GC_THRESHOLD_MAX = 1_000_000_000;
+	private const GC_THRESHOLD_DEFAULT = 10_001;
+	private const GC_THRESHOLD_STEP = 10_000;
+
+	private int $threshold = self::GC_THRESHOLD_DEFAULT;
+	private int $collectionTimeTotalNs = 0;
+
+	private \Logger $logger;
+	private TimingsHandler $timings;
+
+	public function __construct(
+		\Logger $logger,
+		?TimingsHandler $parentTimings,
+	){
+		gc_disable();
+		$this->logger = new \PrefixedLogger($logger, "Cyclic Garbage Collector");
+		$this->timings = new TimingsHandler("Cyclic Garbage Collector", $parentTimings);
+	}
+
+	private function adjustGcThreshold(int $cyclesCollected, int $rootsAfterGC) : void{
+		//TODO Very simple heuristic for dynamic GC buffer resizing:
+		//If there are "too few" collections, increase the collection threshold
+		//by a fixed step
+		//Adapted from zend_gc.c/gc_adjust_threshold() as of PHP 8.3.14
+		if($cyclesCollected < self::GC_THRESHOLD_TRIGGER || $rootsAfterGC >= $this->threshold){
+			$this->threshold = min(self::GC_THRESHOLD_MAX, $this->threshold + self::GC_THRESHOLD_STEP);
+		}elseif($this->threshold > self::GC_THRESHOLD_DEFAULT){
+			$this->threshold = max(self::GC_THRESHOLD_DEFAULT, $this->threshold - self::GC_THRESHOLD_STEP);
+		}
+	}
+
+	public function getThreshold() : int{ return $this->threshold; }
+
+	public function getCollectionTimeTotalNs() : int{ return $this->collectionTimeTotalNs; }
+
+	public function maybeCollectCycles() : int{
+		$rootsBefore = gc_status()["roots"];
+		if($rootsBefore < $this->threshold){
+			return 0;
+		}
+
+		$this->timings->startTiming();
+
+		$start = hrtime(true);
+		$cycles = gc_collect_cycles();
+		$end = hrtime(true);
+
+		$rootsAfter = gc_status()["roots"];
+		$this->adjustGcThreshold($cycles, $rootsAfter);
+
+		$this->timings->stopTiming();
+
+		$time = $end - $start;
+		$this->collectionTimeTotalNs += $time;
+		$this->logger->debug("gc_collect_cycles: " . number_format($time) . " ns ($rootsBefore -> $rootsAfter roots, $cycles cycles collected) - total GC time: " . number_format($this->collectionTimeTotalNs) . " ns");
+
+		return $cycles;
+	}
+}

src/MemoryDump.php

@@ -0,0 +1,305 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ *
+ *
+ */
+
+declare(strict_types=1);
+
+namespace pocketmine;
+
+use pocketmine\utils\Utils;
+use Symfony\Component\Filesystem\Path;
+use function arsort;
+use function count;
+use function fclose;
+use function file_exists;
+use function file_put_contents;
+use function fopen;
+use function fwrite;
+use function gc_disable;
+use function gc_enable;
+use function gc_enabled;
+use function get_class;
+use function get_declared_classes;
+use function get_defined_functions;
+use function ini_get;
+use function ini_set;
+use function is_array;
+use function is_float;
+use function is_object;
+use function is_resource;
+use function is_string;
+use function json_encode;
+use function mkdir;
+use function print_r;
+use function spl_object_hash;
+use function strlen;
+use function substr;
+use const JSON_PRETTY_PRINT;
+use const JSON_THROW_ON_ERROR;
+use const JSON_UNESCAPED_SLASHES;
+use const SORT_NUMERIC;
+
+final class MemoryDump{
+
+	private function __construct(){
+		//NOOP
+	}
+
+	/**
+	 * Static memory dumper accessible from any thread.
+	 */
+	public static function dumpMemory(mixed $startingObject, string $outputFolder, int $maxNesting, int $maxStringSize, \Logger $logger) : void{
+		$hardLimit = Utils::assumeNotFalse(ini_get('memory_limit'), "memory_limit INI directive should always exist");
+		ini_set('memory_limit', '-1');
+		$gcEnabled = gc_enabled();
+		gc_disable();
+
+		if(!file_exists($outputFolder)){
+			mkdir($outputFolder, 0777, true);
+		}
+
+		$obData = Utils::assumeNotFalse(fopen(Path::join($outputFolder, "objects.js"), "wb+"));
+
+		$objects = [];
+
+		$refCounts = [];
+
+		$instanceCounts = [];
+
+		$staticProperties = [];
+		$staticCount = 0;
+
+		$functionStaticVars = [];
+		$functionStaticVarsCount = 0;
+
+		foreach(get_declared_classes() as $className){
+			$reflection = new \ReflectionClass($className);
+			$staticProperties[$className] = [];
+			foreach($reflection->getProperties() as $property){
+				if(!$property->isStatic() || $property->getDeclaringClass()->getName() !== $className){
+					continue;
+				}
+
+				if(!$property->isInitialized()){
+					continue;
+				}
+
+				$staticCount++;
+				$staticProperties[$className][$property->getName()] = self::continueDump($property->getValue(), $objects, $refCounts, 0, $maxNesting, $maxStringSize);
+			}
+
+			if(count($staticProperties[$className]) === 0){
+				unset($staticProperties[$className]);
+			}
+
+			foreach($reflection->getMethods() as $method){
+				if($method->getDeclaringClass()->getName() !== $reflection->getName()){
+					continue;
+				}
+				$methodStatics = [];
+				foreach(Utils::promoteKeys($method->getStaticVariables()) as $name => $variable){
+					$methodStatics[$name] = self::continueDump($variable, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
+				}
+				if(count($methodStatics) > 0){
+					$functionStaticVars[$className . "::" . $method->getName()] = $methodStatics;
+					$functionStaticVarsCount += count($functionStaticVars);
+				}
+			}
+		}
+
+		file_put_contents(Path::join($outputFolder, "staticProperties.js"), json_encode($staticProperties, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
+		$logger->info("Wrote $staticCount static properties");
+
+		$globalVariables = [];
+		$globalCount = 0;
+
+		$ignoredGlobals = [
+			'GLOBALS' => true,
+			'_SERVER' => true,
+			'_REQUEST' => true,
+			'_POST' => true,
+			'_GET' => true,
+			'_FILES' => true,
+			'_ENV' => true,
+			'_COOKIE' => true,
+			'_SESSION' => true
+		];
+
+		foreach(Utils::promoteKeys($GLOBALS) as $varName => $value){
+			if(isset($ignoredGlobals[$varName])){
+				continue;
+			}
+
+			$globalCount++;
+			$globalVariables[$varName] = self::continueDump($value, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
+		}
+
+		file_put_contents(Path::join($outputFolder, "globalVariables.js"), json_encode($globalVariables, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
+		$logger->info("Wrote $globalCount global variables");
+
+		foreach(get_defined_functions()["user"] as $function){
+			$reflect = new \ReflectionFunction($function);
+
+			$vars = [];
+			foreach(Utils::promoteKeys($reflect->getStaticVariables()) as $varName => $variable){
+				$vars[$varName] = self::continueDump($variable, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
+			}
+			if(count($vars) > 0){
+				$functionStaticVars[$function] = $vars;
+				$functionStaticVarsCount += count($vars);
+			}
+		}
+		file_put_contents(Path::join($outputFolder, 'functionStaticVars.js'), json_encode($functionStaticVars, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
+		$logger->info("Wrote $functionStaticVarsCount function static variables");
+
+		$data = self::continueDump($startingObject, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
+
+		do{
+			$continue = false;
+			foreach(Utils::stringifyKeys($objects) as $hash => $object){
+				if(!is_object($object)){
+					continue;
+				}
+				$continue = true;
+
+				$className = get_class($object);
+				if(!isset($instanceCounts[$className])){
+					$instanceCounts[$className] = 1;
+				}else{
+					$instanceCounts[$className]++;
+				}
+
+				$objects[$hash] = true;
+				$info = [
+					"information" => "$hash@$className",
+				];
+				if($object instanceof \Closure){
+					$info["definition"] = Utils::getNiceClosureName($object);
+					$info["referencedVars"] = [];
+					$reflect = new \ReflectionFunction($object);
+					if(($closureThis = $reflect->getClosureThis()) !== null){
+						$info["this"] = self::continueDump($closureThis, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
+					}
+
+					foreach(Utils::promoteKeys($reflect->getStaticVariables()) as $name => $variable){
+						$info["referencedVars"][$name] = self::continueDump($variable, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
+					}
+				}else{
+					$reflection = new \ReflectionObject($object);
+
+					$info["properties"] = [];
+
+					for($original = $reflection; $reflection !== false; $reflection = $reflection->getParentClass()){
+						foreach($reflection->getProperties() as $property){
+							if($property->isStatic()){
+								continue;
+							}
+
+							$name = $property->getName();
+							if($reflection !== $original){
+								if($property->isPrivate()){
+									$name = $reflection->getName() . ":" . $name;
+								}else{
+									continue;
+								}
+							}
+							if(!$property->isInitialized($object)){
+								continue;
+							}
+
+							$info["properties"][$name] = self::continueDump($property->getValue($object), $objects, $refCounts, 0, $maxNesting, $maxStringSize);
+						}
+					}
+				}
+
+				fwrite($obData, json_encode($info, JSON_UNESCAPED_SLASHES | JSON_THROW_ON_ERROR) . "\n");
+			}
+
+		}while($continue);
+
+		$logger->info("Wrote " . count($objects) . " objects");
+
+		fclose($obData);
+
+		file_put_contents(Path::join($outputFolder, "serverEntry.js"), json_encode($data, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
+		file_put_contents(Path::join($outputFolder, "referenceCounts.js"), json_encode($refCounts, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
+
+		arsort($instanceCounts, SORT_NUMERIC);
+		file_put_contents(Path::join($outputFolder, "instanceCounts.js"), json_encode($instanceCounts, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
+
+		$logger->info("Finished!");
+
+		ini_set('memory_limit', $hardLimit);
+		if($gcEnabled){
+			gc_enable();
+		}
+	}
+
+	/**
+	 * @param object[] $objects   reference parameter
+	 * @param int[]    $refCounts reference parameter
+	 *
+	 * @phpstan-param array<string, object> $objects
+	 * @phpstan-param array<string, int> $refCounts
+	 * @phpstan-param-out array<string, object> $objects
+	 * @phpstan-param-out array<string, int> $refCounts
+	 */
+	private static function continueDump(mixed $from, array &$objects, array &$refCounts, int $recursion, int $maxNesting, int $maxStringSize) : mixed{
+		if($maxNesting <= 0){
+			return "(error) NESTING LIMIT REACHED";
+		}
+
+		--$maxNesting;
+
+		if(is_object($from)){
+			if(!isset($objects[$hash = spl_object_hash($from)])){
+				$objects[$hash] = $from;
+				$refCounts[$hash] = 0;
+			}
+
+			++$refCounts[$hash];
+
+			$data = "(object) $hash";
+		}elseif(is_array($from)){
+			if($recursion >= 5){
+				return "(error) ARRAY RECURSION LIMIT REACHED";
+			}
+			$data = [];
+			$numeric = 0;
+			foreach(Utils::promoteKeys($from) as $key => $value){
+				$data[$numeric] = [
+					"k" => self::continueDump($key, $objects, $refCounts, $recursion + 1, $maxNesting, $maxStringSize),
+					"v" => self::continueDump($value, $objects, $refCounts, $recursion + 1, $maxNesting, $maxStringSize),
+				];
+				$numeric++;
+			}
+		}elseif(is_string($from)){
+			$data = "(string) len(" . strlen($from) . ") " . substr(Utils::printable($from), 0, $maxStringSize);
+		}elseif(is_resource($from)){
+			$data = "(resource) " . print_r($from, true);
+		}elseif(is_float($from)){
+			$data = "(float) $from";
+		}else{
+			$data = $from;
+		}
+
+		return $data;
+	}
+}

src/MemoryManager.php

@@ -29,52 +29,24 @@ use pocketmine\scheduler\DumpWorkerMemoryTask;
 use pocketmine\scheduler\GarbageCollectionTask;
 use pocketmine\timings\Timings;
 use pocketmine\utils\Process;
-use pocketmine\utils\Utils;
 use pocketmine\YmlServerProperties as Yml;
-use Symfony\Component\Filesystem\Path;
-use function arsort;
-use function count;
-use function fclose;
-use function file_exists;
-use function file_put_contents;
-use function fopen;
-use function fwrite;
 use function gc_collect_cycles;
-use function gc_disable;
-use function gc_enable;
 use function gc_mem_caches;
-use function get_class;
-use function get_declared_classes;
-use function get_defined_functions;
-use function ini_get;
 use function ini_set;
 use function intdiv;
-use function is_array;
-use function is_float;
-use function is_object;
-use function is_resource;
-use function is_string;
-use function json_encode;
 use function mb_strtoupper;
 use function min;
-use function mkdir;
 use function preg_match;
-use function print_r;
 use function round;
-use function spl_object_hash;
 use function sprintf;
-use function strlen;
-use function substr;
-use const JSON_PRETTY_PRINT;
-use const JSON_THROW_ON_ERROR;
-use const JSON_UNESCAPED_SLASHES;
-use const SORT_NUMERIC;
 
 class MemoryManager{
 	private const DEFAULT_CHECK_RATE = Server::TARGET_TICKS_PER_SECOND;
 	private const DEFAULT_CONTINUOUS_TRIGGER_RATE = Server::TARGET_TICKS_PER_SECOND * 2;
 	private const DEFAULT_TICKS_PER_GC = 30 * 60 * Server::TARGET_TICKS_PER_SECOND;
 
+	private GarbageCollectorManager $cycleGcManager;
+
 	private int $memoryLimit;
 	private int $globalMemoryLimit;
 	private int $checkRate;
@@ -88,14 +60,8 @@ class MemoryManager{
 
 	private int $garbageCollectionPeriod;
 	private int $garbageCollectionTicker = 0;
-	private bool $garbageCollectionTrigger;
-	private bool $garbageCollectionAsync;
 
 	private int $lowMemChunkRadiusOverride;
-	private bool $lowMemChunkGC;
-
-	private bool $lowMemDisableChunkCache;
-	private bool $lowMemClearWorldCache;
 
 	private bool $dumpWorkers = true;
 
@@ -105,6 +71,7 @@ class MemoryManager{
 		private Server $server
 	){
 		$this->logger = new \PrefixedLogger($server->getLogger(), "Memory Manager");
+		$this->cycleGcManager = new GarbageCollectorManager($this->logger, Timings::$memoryManager);
 
 		$this->init($server->getConfigGroup());
 	}
@@ -142,17 +109,10 @@ class MemoryManager{
 		$this->continuousTriggerRate = $config->getPropertyInt(Yml::MEMORY_CONTINUOUS_TRIGGER_RATE, self::DEFAULT_CONTINUOUS_TRIGGER_RATE);
 
 		$this->garbageCollectionPeriod = $config->getPropertyInt(Yml::MEMORY_GARBAGE_COLLECTION_PERIOD, self::DEFAULT_TICKS_PER_GC);
-		$this->garbageCollectionTrigger = $config->getPropertyBool(Yml::MEMORY_GARBAGE_COLLECTION_LOW_MEMORY_TRIGGER, true);
-		$this->garbageCollectionAsync = $config->getPropertyBool(Yml::MEMORY_GARBAGE_COLLECTION_COLLECT_ASYNC_WORKER, true);
 
 		$this->lowMemChunkRadiusOverride = $config->getPropertyInt(Yml::MEMORY_MAX_CHUNKS_CHUNK_RADIUS, 4);
-		$this->lowMemChunkGC = $config->getPropertyBool(Yml::MEMORY_MAX_CHUNKS_TRIGGER_CHUNK_COLLECT, true);
-
-		$this->lowMemDisableChunkCache = $config->getPropertyBool(Yml::MEMORY_WORLD_CACHES_DISABLE_CHUNK_CACHE, true);
-		$this->lowMemClearWorldCache = $config->getPropertyBool(Yml::MEMORY_WORLD_CACHES_LOW_MEMORY_TRIGGER, true);
 
 		$this->dumpWorkers = $config->getPropertyBool(Yml::MEMORY_MEMORY_DUMP_DUMP_ASYNC_WORKER, true);
-		gc_enable();
 	}
 
 	public function isLowMemory() : bool{
@@ -163,8 +123,11 @@ class MemoryManager{
 		return $this->globalMemoryLimit;
 	}
 
+	/**
+	 * @deprecated
+	 */
 	public function canUseChunkCache() : bool{
-		return !$this->lowMemory || !$this->lowMemDisableChunkCache;
+		return !$this->lowMemory;
 	}
 
 	/**
@@ -180,26 +143,19 @@ class MemoryManager{
 	public function trigger(int $memory, int $limit, bool $global = false, int $triggerCount = 0) : void{
 		$this->logger->debug(sprintf("%sLow memory triggered, limit %gMB, using %gMB",
 			$global ? "Global " : "", round(($limit / 1024) / 1024, 2), round(($memory / 1024) / 1024, 2)));
-		if($this->lowMemClearWorldCache){
+		foreach($this->server->getWorldManager()->getWorlds() as $world){
-			foreach($this->server->getWorldManager()->getWorlds() as $world){
+			$world->clearCache(true);
-				$world->clearCache(true);
-			}
-			ChunkCache::pruneCaches();
 		}
+		ChunkCache::pruneCaches();
 
-		if($this->lowMemChunkGC){
+		foreach($this->server->getWorldManager()->getWorlds() as $world){
-			foreach($this->server->getWorldManager()->getWorlds() as $world){
+			$world->doChunkGarbageCollection();
-				$world->doChunkGarbageCollection();
-			}
 		}
 
 		$ev = new LowMemoryEvent($memory, $limit, $global, $triggerCount);
 		$ev->call();
 
-		$cycles = 0;
+		$cycles = $this->triggerGarbageCollector();
-		if($this->garbageCollectionTrigger){
-			$cycles = $this->triggerGarbageCollector();
-		}
 
 		$this->logger->debug(sprintf("Freed %gMB, $cycles cycles", round(($ev->getMemoryFreed() / 1024) / 1024, 2)));
 	}
@@ -239,6 +195,8 @@ class MemoryManager{
 		if($this->garbageCollectionPeriod > 0 && ++$this->garbageCollectionTicker >= $this->garbageCollectionPeriod){
 			$this->garbageCollectionTicker = 0;
 			$this->triggerGarbageCollector();
+		}else{
+			$this->cycleGcManager->maybeCollectCycles();
 		}
 
 		Timings::$memoryManager->stopTiming();
@@ -247,14 +205,12 @@ class MemoryManager{
 	public function triggerGarbageCollector() : int{
 		Timings::$garbageCollector->startTiming();
 
-		if($this->garbageCollectionAsync){
+		$pool = $this->server->getAsyncPool();
-			$pool = $this->server->getAsyncPool();
+		if(($w = $pool->shutdownUnusedWorkers()) > 0){
-			if(($w = $pool->shutdownUnusedWorkers()) > 0){
+			$this->logger->debug("Shut down $w idle async pool workers");
-				$this->logger->debug("Shut down $w idle async pool workers");
+		}
-			}
+		foreach($pool->getRunningWorkers() as $i){
-			foreach($pool->getRunningWorkers() as $i){
+			$pool->submitTaskToWorker(new GarbageCollectionTask(), $i);
-				$pool->submitTaskToWorker(new GarbageCollectionTask(), $i);
-			}
 		}
 
 		$cycles = gc_collect_cycles();
@@ -271,7 +227,7 @@ class MemoryManager{
 	public function dumpServerMemory(string $outputFolder, int $maxNesting, int $maxStringSize) : void{
 		$logger = new \PrefixedLogger($this->server->getLogger(), "Memory Dump");
 		$logger->notice("After the memory dump is done, the server might crash");
-		self::dumpMemory($this->server, $outputFolder, $maxNesting, $maxStringSize, $logger);
+		MemoryDump::dumpMemory($this->server, $outputFolder, $maxNesting, $maxStringSize, $logger);
 
 		if($this->dumpWorkers){
 			$pool = $this->server->getAsyncPool();
@@ -283,239 +239,10 @@ class MemoryManager{
 
 	/**
 	 * Static memory dumper accessible from any thread.
+	 * @deprecated
+	 * @see MemoryDump
 	 */
 	public static function dumpMemory(mixed $startingObject, string $outputFolder, int $maxNesting, int $maxStringSize, \Logger $logger) : void{
-		$hardLimit = Utils::assumeNotFalse(ini_get('memory_limit'), "memory_limit INI directive should always exist");
+		MemoryDump::dumpMemory($startingObject, $outputFolder, $maxNesting, $maxStringSize, $logger);
-		ini_set('memory_limit', '-1');
-		gc_disable();
-
-		if(!file_exists($outputFolder)){
-			mkdir($outputFolder, 0777, true);
-		}
-
-		$obData = Utils::assumeNotFalse(fopen(Path::join($outputFolder, "objects.js"), "wb+"));
-
-		$objects = [];
-
-		$refCounts = [];
-
-		$instanceCounts = [];
-
-		$staticProperties = [];
-		$staticCount = 0;
-
-		$functionStaticVars = [];
-		$functionStaticVarsCount = 0;
-
-		foreach(get_declared_classes() as $className){
-			$reflection = new \ReflectionClass($className);
-			$staticProperties[$className] = [];
-			foreach($reflection->getProperties() as $property){
-				if(!$property->isStatic() || $property->getDeclaringClass()->getName() !== $className){
-					continue;
-				}
-
-				if(!$property->isInitialized()){
-					continue;
-				}
-
-				$staticCount++;
-				$staticProperties[$className][$property->getName()] = self::continueDump($property->getValue(), $objects, $refCounts, 0, $maxNesting, $maxStringSize);
-			}
-
-			if(count($staticProperties[$className]) === 0){
-				unset($staticProperties[$className]);
-			}
-
-			foreach($reflection->getMethods() as $method){
-				if($method->getDeclaringClass()->getName() !== $reflection->getName()){
-					continue;
-				}
-				$methodStatics = [];
-				foreach(Utils::promoteKeys($method->getStaticVariables()) as $name => $variable){
-					$methodStatics[$name] = self::continueDump($variable, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
-				}
-				if(count($methodStatics) > 0){
-					$functionStaticVars[$className . "::" . $method->getName()] = $methodStatics;
-					$functionStaticVarsCount += count($functionStaticVars);
-				}
-			}
-		}
-
-		file_put_contents(Path::join($outputFolder, "staticProperties.js"), json_encode($staticProperties, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
-		$logger->info("Wrote $staticCount static properties");
-
-		$globalVariables = [];
-		$globalCount = 0;
-
-		$ignoredGlobals = [
-			'GLOBALS' => true,
-			'_SERVER' => true,
-			'_REQUEST' => true,
-			'_POST' => true,
-			'_GET' => true,
-			'_FILES' => true,
-			'_ENV' => true,
-			'_COOKIE' => true,
-			'_SESSION' => true
-		];
-
-		foreach(Utils::promoteKeys($GLOBALS) as $varName => $value){
-			if(isset($ignoredGlobals[$varName])){
-				continue;
-			}
-
-			$globalCount++;
-			$globalVariables[$varName] = self::continueDump($value, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
-		}
-
-		file_put_contents(Path::join($outputFolder, "globalVariables.js"), json_encode($globalVariables, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
-		$logger->info("Wrote $globalCount global variables");
-
-		foreach(get_defined_functions()["user"] as $function){
-			$reflect = new \ReflectionFunction($function);
-
-			$vars = [];
-			foreach(Utils::promoteKeys($reflect->getStaticVariables()) as $varName => $variable){
-				$vars[$varName] = self::continueDump($variable, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
-			}
-			if(count($vars) > 0){
-				$functionStaticVars[$function] = $vars;
-				$functionStaticVarsCount += count($vars);
-			}
-		}
-		file_put_contents(Path::join($outputFolder, 'functionStaticVars.js'), json_encode($functionStaticVars, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
-		$logger->info("Wrote $functionStaticVarsCount function static variables");
-
-		$data = self::continueDump($startingObject, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
-
-		do{
-			$continue = false;
-			foreach(Utils::stringifyKeys($objects) as $hash => $object){
-				if(!is_object($object)){
-					continue;
-				}
-				$continue = true;
-
-				$className = get_class($object);
-				if(!isset($instanceCounts[$className])){
-					$instanceCounts[$className] = 1;
-				}else{
-					$instanceCounts[$className]++;
-				}
-
-				$objects[$hash] = true;
-				$info = [
-					"information" => "$hash@$className",
-				];
-				if($object instanceof \Closure){
-					$info["definition"] = Utils::getNiceClosureName($object);
-					$info["referencedVars"] = [];
-					$reflect = new \ReflectionFunction($object);
-					if(($closureThis = $reflect->getClosureThis()) !== null){
-						$info["this"] = self::continueDump($closureThis, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
-					}
-
-					foreach(Utils::promoteKeys($reflect->getStaticVariables()) as $name => $variable){
-						$info["referencedVars"][$name] = self::continueDump($variable, $objects, $refCounts, 0, $maxNesting, $maxStringSize);
-					}
-				}else{
-					$reflection = new \ReflectionObject($object);
-
-					$info["properties"] = [];
-
-					for($original = $reflection; $reflection !== false; $reflection = $reflection->getParentClass()){
-						foreach($reflection->getProperties() as $property){
-							if($property->isStatic()){
-								continue;
-							}
-
-							$name = $property->getName();
-							if($reflection !== $original){
-								if($property->isPrivate()){
-									$name = $reflection->getName() . ":" . $name;
-								}else{
-									continue;
-								}
-							}
-							if(!$property->isInitialized($object)){
-								continue;
-							}
-
-							$info["properties"][$name] = self::continueDump($property->getValue($object), $objects, $refCounts, 0, $maxNesting, $maxStringSize);
-						}
-					}
-				}
-
-				fwrite($obData, json_encode($info, JSON_UNESCAPED_SLASHES | JSON_THROW_ON_ERROR) . "\n");
-			}
-
-		}while($continue);
-
-		$logger->info("Wrote " . count($objects) . " objects");
-
-		fclose($obData);
-
-		file_put_contents(Path::join($outputFolder, "serverEntry.js"), json_encode($data, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
-		file_put_contents(Path::join($outputFolder, "referenceCounts.js"), json_encode($refCounts, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
-
-		arsort($instanceCounts, SORT_NUMERIC);
-		file_put_contents(Path::join($outputFolder, "instanceCounts.js"), json_encode($instanceCounts, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR));
-
-		$logger->info("Finished!");
-
-		ini_set('memory_limit', $hardLimit);
-		gc_enable();
-	}
-
-	/**
-	 * @param object[] $objects   reference parameter
-	 * @param int[]    $refCounts reference parameter
-	 *
-	 * @phpstan-param array<string, object> $objects
-	 * @phpstan-param array<string, int> $refCounts
-	 * @phpstan-param-out array<string, object> $objects
-	 * @phpstan-param-out array<string, int> $refCounts
-	 */
-	private static function continueDump(mixed $from, array &$objects, array &$refCounts, int $recursion, int $maxNesting, int $maxStringSize) : mixed{
-		if($maxNesting <= 0){
-			return "(error) NESTING LIMIT REACHED";
-		}
-
-		--$maxNesting;
-
-		if(is_object($from)){
-			if(!isset($objects[$hash = spl_object_hash($from)])){
-				$objects[$hash] = $from;
-				$refCounts[$hash] = 0;
-			}
-
-			++$refCounts[$hash];
-
-			$data = "(object) $hash";
-		}elseif(is_array($from)){
-			if($recursion >= 5){
-				return "(error) ARRAY RECURSION LIMIT REACHED";
-			}
-			$data = [];
-			$numeric = 0;
-			foreach(Utils::promoteKeys($from) as $key => $value){
-				$data[$numeric] = [
-					"k" => self::continueDump($key, $objects, $refCounts, $recursion + 1, $maxNesting, $maxStringSize),
-					"v" => self::continueDump($value, $objects, $refCounts, $recursion + 1, $maxNesting, $maxStringSize),
-				];
-				$numeric++;
-			}
-		}elseif(is_string($from)){
-			$data = "(string) len(" . strlen($from) . ") " . substr(Utils::printable($from), 0, $maxStringSize);
-		}elseif(is_resource($from)){
-			$data = "(resource) " . print_r($from, true);
-		}elseif(is_float($from)){
-			$data = "(float) $from";
-		}else{
-			$data = $from;
-		}
-
-		return $data;
 	}
 }

src/YmlServerProperties.php

@@ -75,20 +75,14 @@ final class YmlServerProperties{
 	public const MEMORY_CONTINUOUS_TRIGGER = 'memory.continuous-trigger';
 	public const MEMORY_CONTINUOUS_TRIGGER_RATE = 'memory.continuous-trigger-rate';
 	public const MEMORY_GARBAGE_COLLECTION = 'memory.garbage-collection';
-	public const MEMORY_GARBAGE_COLLECTION_COLLECT_ASYNC_WORKER = 'memory.garbage-collection.collect-async-worker';
-	public const MEMORY_GARBAGE_COLLECTION_LOW_MEMORY_TRIGGER = 'memory.garbage-collection.low-memory-trigger';
 	public const MEMORY_GARBAGE_COLLECTION_PERIOD = 'memory.garbage-collection.period';
 	public const MEMORY_GLOBAL_LIMIT = 'memory.global-limit';
 	public const MEMORY_MAIN_HARD_LIMIT = 'memory.main-hard-limit';
 	public const MEMORY_MAIN_LIMIT = 'memory.main-limit';
 	public const MEMORY_MAX_CHUNKS = 'memory.max-chunks';
 	public const MEMORY_MAX_CHUNKS_CHUNK_RADIUS = 'memory.max-chunks.chunk-radius';
-	public const MEMORY_MAX_CHUNKS_TRIGGER_CHUNK_COLLECT = 'memory.max-chunks.trigger-chunk-collect';
 	public const MEMORY_MEMORY_DUMP = 'memory.memory-dump';
 	public const MEMORY_MEMORY_DUMP_DUMP_ASYNC_WORKER = 'memory.memory-dump.dump-async-worker';
-	public const MEMORY_WORLD_CACHES = 'memory.world-caches';
-	public const MEMORY_WORLD_CACHES_DISABLE_CHUNK_CACHE = 'memory.world-caches.disable-chunk-cache';
-	public const MEMORY_WORLD_CACHES_LOW_MEMORY_TRIGGER = 'memory.world-caches.low-memory-trigger';
 	public const NETWORK = 'network';
 	public const NETWORK_ASYNC_COMPRESSION = 'network.async-compression';
 	public const NETWORK_ASYNC_COMPRESSION_THRESHOLD = 'network.async-compression-threshold';

src/network/mcpe/raklib/RakLibServer.php

@@ -82,7 +82,11 @@ class RakLibServer extends Thread{
 	}
 
 	protected function onRun() : void{
+		//TODO: switch to manually triggered GC
+		//the best time to do it is between ticks when the server would otherwise be sleeping, but RakLib's current
+		//design doesn't allow this as of 1.1.1
 		gc_enable();
+
 		ini_set("display_errors", '1');
 		ini_set("display_startup_errors", '1');
 		\GlobalLogger::set($this->logger);

src/scheduler/AsyncTask.php

@@ -93,6 +93,7 @@ abstract class AsyncTask extends Runnable{
 
 		$this->finished = true;
 		AsyncWorker::getNotifier()->wakeupSleeper();
+		AsyncWorker::maybeCollectCycles();
 	}
 
 	/**

src/scheduler/AsyncWorker.php

@@ -24,12 +24,13 @@ declare(strict_types=1);
 namespace pocketmine\scheduler;
 
 use pmmp\thread\Thread as NativeThread;
+use pocketmine\GarbageCollectorManager;
 use pocketmine\snooze\SleeperHandlerEntry;
 use pocketmine\snooze\SleeperNotifier;
 use pocketmine\thread\log\ThreadSafeLogger;
 use pocketmine\thread\Worker;
+use pocketmine\timings\Timings;
 use pocketmine\utils\AssumptionFailedError;
-use function gc_enable;
 use function ini_set;
 
 class AsyncWorker extends Worker{
@@ -37,6 +38,7 @@ class AsyncWorker extends Worker{
 	private static array $store = [];
 
 	private static ?SleeperNotifier $notifier = null;
+	private static ?GarbageCollectorManager $cycleGcManager = null;
 
 	public function __construct(
 		private ThreadSafeLogger $logger,
@@ -52,11 +54,16 @@ class AsyncWorker extends Worker{
 		throw new AssumptionFailedError("SleeperNotifier not found in thread-local storage");
 	}
 
+	public static function maybeCollectCycles() : void{
+		if(self::$cycleGcManager === null){
+			throw new AssumptionFailedError("GarbageCollectorManager not found in thread-local storage");
+		}
+		self::$cycleGcManager->maybeCollectCycles();
+	}
+
 	protected function onRun() : void{
 		\GlobalLogger::set($this->logger);
 
-		gc_enable();
-
 		if($this->memoryLimit > 0){
 			ini_set('memory_limit', $this->memoryLimit . 'M');
 			$this->logger->debug("Set memory limit to " . $this->memoryLimit . " MB");
@@ -66,6 +73,7 @@ class AsyncWorker extends Worker{
 		}
 
 		self::$notifier = $this->sleeperEntry->createNotifier();
+		self::$cycleGcManager = new GarbageCollectorManager($this->logger, Timings::$asyncTaskWorkers);
 	}
 
 	public function getLogger() : ThreadSafeLogger{

src/scheduler/DumpWorkerMemoryTask.php

@@ -24,7 +24,7 @@ declare(strict_types=1);
 namespace pocketmine\scheduler;
 
 use pmmp\thread\Thread as NativeThread;
-use pocketmine\MemoryManager;
+use pocketmine\MemoryDump;
 use Symfony\Component\Filesystem\Path;
 use function assert;
 
@@ -41,7 +41,7 @@ class DumpWorkerMemoryTask extends AsyncTask{
 	public function onRun() : void{
 		$worker = NativeThread::getCurrentThread();
 		assert($worker instanceof AsyncWorker);
-		MemoryManager::dumpMemory(
+		MemoryDump::dumpMemory(
 			$worker,
 			Path::join($this->outputFolder, "AsyncWorker#" . $worker->getAsyncWorkerId()),
 			$this->maxNesting,

src/timings/Timings.php

@@ -131,7 +131,7 @@ abstract class Timings{
 	/** @var TimingsHandler[] */
 	private static array $asyncTaskError = [];
 
-	private static TimingsHandler $asyncTaskWorkers;
+	public static TimingsHandler $asyncTaskWorkers;
 	/** @var TimingsHandler[] */
 	private static array $asyncTaskRun = [];
 

src/world/World.php

@@ -167,6 +167,9 @@ class World implements ChunkManager{
 
 	public const DEFAULT_TICKED_BLOCKS_PER_SUBCHUNK_PER_TICK = 3;
 
+	//TODO: this could probably do with being a lot bigger
+	private const BLOCK_CACHE_SIZE_CAP = 2048;
+
 	/**
 	 * @var Player[] entity runtime ID => Player
 	 * @phpstan-var array<int, Player>
@@ -202,6 +205,7 @@ class World implements ChunkManager{
 	 * @phpstan-var array<ChunkPosHash, array<ChunkBlockPosHash, Block>>
 	 */
 	private array $blockCache = [];
+	private int $blockCacheSize = 0;
 	/**
 	 * @var AxisAlignedBB[][][] chunkHash => [relativeBlockHash => AxisAlignedBB[]]
 	 * @phpstan-var array<ChunkPosHash, array<ChunkBlockPosHash, list<AxisAlignedBB>>>
@@ -653,6 +657,7 @@ class World implements ChunkManager{
 
 		$this->provider->close();
 		$this->blockCache = [];
+		$this->blockCacheSize = 0;
 		$this->blockCollisionBoxCache = [];
 
 		$this->unloaded = true;
@@ -1138,13 +1143,16 @@ class World implements ChunkManager{
 	public function clearCache(bool $force = false) : void{
 		if($force){
 			$this->blockCache = [];
+			$this->blockCacheSize = 0;
 			$this->blockCollisionBoxCache = [];
 		}else{
-			$count = 0;
+			//Recalculate this when we're asked - blockCacheSize may be higher than the real size
+			$this->blockCacheSize = 0;
 			foreach($this->blockCache as $list){
-				$count += count($list);
+				$this->blockCacheSize += count($list);
-				if($count > 2048){
+				if($this->blockCacheSize > self::BLOCK_CACHE_SIZE_CAP){
 					$this->blockCache = [];
+					$this->blockCacheSize = 0;
 					break;
 				}
 			}
@@ -1152,7 +1160,7 @@ class World implements ChunkManager{
 			$count = 0;
 			foreach($this->blockCollisionBoxCache as $list){
 				$count += count($list);
-				if($count > 2048){
+				if($count > self::BLOCK_CACHE_SIZE_CAP){
 					//TODO: Is this really the best logic?
 					$this->blockCollisionBoxCache = [];
 					break;
@@ -1161,6 +1169,19 @@ class World implements ChunkManager{
 		}
 	}
 
+	private function trimBlockCache() : void{
+		$before = $this->blockCacheSize;
+		//Since PHP maintains key order, earliest in foreach should be the oldest entries
+		//Older entries are less likely to be hot, so destroying these should usually have the lowest impact on performance
+		foreach($this->blockCache as $chunkHash => $blocks){
+			unset($this->blockCache[$chunkHash]);
+			$this->blockCacheSize -= count($blocks);
+			if($this->blockCacheSize < self::BLOCK_CACHE_SIZE_CAP){
+				break;
+			}
+		}
+	}
+
 	/**
 	 * @return true[] fullID => dummy
 	 * @phpstan-return array<int, true>
@@ -1921,6 +1942,10 @@ class World implements ChunkManager{
 
 		if($addToCache && $relativeBlockHash !== null){
 			$this->blockCache[$chunkHash][$relativeBlockHash] = $block;
+
+			if(++$this->blockCacheSize >= self::BLOCK_CACHE_SIZE_CAP){
+				$this->trimBlockCache();
+			}
 		}
 
 		return $block;
@@ -1967,6 +1992,7 @@ class World implements ChunkManager{
 		$relativeBlockHash = World::chunkBlockHash($x, $y, $z);
 
 		unset($this->blockCache[$chunkHash][$relativeBlockHash]);
+		$this->blockCacheSize--;
 		unset($this->blockCollisionBoxCache[$chunkHash][$relativeBlockHash]);
 		//blocks like fences have collision boxes that reach into neighbouring blocks, so we need to invalidate the
 		//caches for those blocks as well
@@ -2570,6 +2596,7 @@ class World implements ChunkManager{
 
 		$this->chunks[$chunkHash] = $chunk;
 
+		$this->blockCacheSize -= count($this->blockCache[$chunkHash] ?? []);
 		unset($this->blockCache[$chunkHash]);
 		unset($this->blockCollisionBoxCache[$chunkHash]);
 		unset($this->changedBlocks[$chunkHash]);
@@ -2854,6 +2881,8 @@ class World implements ChunkManager{
 			$this->logger->debug("Chunk $x $z has been upgraded, will be saved at the next autosave opportunity");
 		}
 		$this->chunks[$chunkHash] = $chunk;
+
+		$this->blockCacheSize -= count($this->blockCache[$chunkHash] ?? []);
 		unset($this->blockCache[$chunkHash]);
 		unset($this->blockCollisionBoxCache[$chunkHash]);
 
@@ -3013,6 +3042,7 @@ class World implements ChunkManager{
 		}
 
 		unset($this->chunks[$chunkHash]);
+		$this->blockCacheSize -= count($this->blockCache[$chunkHash] ?? []);
 		unset($this->blockCache[$chunkHash]);
 		unset($this->blockCollisionBoxCache[$chunkHash]);
 		unset($this->changedBlocks[$chunkHash]);