From 17a3de38bcef4c1e75a41927e195374de57df0f4 Mon Sep 17 00:00:00 2001
From: DBotThePony <dbotthepony@yandex.ru>
Date: Mon, 22 Apr 2024 16:39:38 +0700
Subject: [PATCH] Improvements to scheduling inside blockable event loop

---
 .../kstarbound/util/BlockableEventLoop.kt     | 27 ++++++++++---------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/util/BlockableEventLoop.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/util/BlockableEventLoop.kt
index 177a476f..171c816b 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/util/BlockableEventLoop.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/util/BlockableEventLoop.kt
@@ -107,9 +107,9 @@ open class BlockableEventLoop(name: String) : Thread(name), ScheduledExecutorSer
 
 	private fun eventLoopIteration(): Boolean {
 		var executedAnything = false
-		val next = eventQueue.poll()
+		var next = eventQueue.poll()
 
-		if (next != null) {
+		while (next != null) {
 			executedAnything = true
 
 			try {
@@ -127,24 +127,25 @@ open class BlockableEventLoop(name: String) : Thread(name), ScheduledExecutorSer
 					LOGGER.error("Caught an exception while propagating CompletableFuture to completeExceptionally stage", err)
 				}
 			}
+
+			// keep executing queued tasks until we hit scheduled task deadline
+			if (scheduledQueue.isEmpty() || scheduledQueue.peek()!!.executeAt > System.nanoTime())
+				next = eventQueue.poll()
+			else
+				next = null
 		}
 
 		if (scheduledQueue.isNotEmpty()) {
 			val executed = ObjectArrayList<ScheduledTask<*>>(4)
-			var lastSize: Int
 
-			do {
-				lastSize = executed.size
+			while (scheduledQueue.isNotEmpty() && (isShutdown || scheduledQueue.peek()!!.executeAt <= System.nanoTime())) {
+				executedAnything = true
+				val poll = scheduledQueue.poll()!!
 
-				while (scheduledQueue.isNotEmpty() && (isShutdown || scheduledQueue.peek()!!.executeAt <= System.nanoTime())) {
-					executedAnything = true
-					val poll = scheduledQueue.poll()!!
-
-					if (poll.perform(isShutdown)) {
-						executed.add(poll)
-					}
+				if (poll.perform(isShutdown)) {
+					executed.add(poll)
 				}
-			} while (lastSize != executed.size)
+			}
 
 			scheduledQueue.addAll(executed)
 		}