From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Aikar Date: Mon, 4 May 2020 01:08:56 -0400 Subject: [PATCH] Set cap on JDK per-thread native byte buffer cache See: https://www.evanjones.ca/java-bytebuffer-leak.html This is potentially a source of lots of native memory usage. We are clearly seeing native usage upwards to 1-4GB which doesn't make sense. Region File usage fixed in previous patch should of tecnically only been somewhat temporary until GC finally gets it some time later, but between all the various plugins doing IO on various threads, this hidden detail of the JDK could be keeping long lived large direct buffers in cache. Set system properly at server startup if not set already to help protect from this. diff --git a/src/main/java/org/bukkit/craftbukkit/Main.java b/src/main/java/org/bukkit/craftbukkit/Main.java index 5e79ad04aed13462d1d187a71801aeb2628495e8..344d93f1d7f25a3f26064469e78dd698af66dc0d 100644 --- a/src/main/java/org/bukkit/craftbukkit/Main.java +++ b/src/main/java/org/bukkit/craftbukkit/Main.java @@ -28,6 +28,7 @@ public class Main { } // Paper end // Todo: Installation script + if (System.getProperty("jdk.nio.maxCachedBufferSize") == null) System.setProperty("jdk.nio.maxCachedBufferSize", "262144"); // Paper - cap per-thread NIO cache size OptionParser parser = new OptionParser() { { acceptsAll(Main.asList("?", "help"), "Show the help");