use monotonic time for all local timers

DenizenScript · Apr 21, 2022 · 5d17775 · 5d17775
1 parent adb3d84
commit 5d17775
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Showing 10 changed files with 37 additions and 16 deletions.
diff --git a/src/main/java/com/denizenscript/denizencore/DenizenCore.java b/src/main/java/com/denizenscript/denizencore/DenizenCore.java
@@ -15,6 +15,7 @@
 import com.denizenscript.denizencore.tags.Attribute;
 import com.denizenscript.denizencore.tags.ReplaceableTagEvent;
 import com.denizenscript.denizencore.tags.TagManager;
+import com.denizenscript.denizencore.utilities.CoreUtilities;
 import com.denizenscript.denizencore.utilities.debugging.LogInterceptor;
 import com.denizenscript.denizencore.utilities.debugging.Debug;
 import com.denizenscript.denizencore.utilities.scheduling.Schedulable;
@@ -46,17 +47,17 @@ public class DenizenCore {
     public static ScriptEngine scriptEngine;
 
     /**
-     * Time (System.currentTimeMillis) that the engine first loaded.
+     * Monotonic time (CoreUtilities.monotonicMillis) that the engine first loaded.
      */
-    public final static long startTime = System.currentTimeMillis();
+    public final static long startTime = CoreUtilities.monotonicMillis();
 
     /**
      * Server flags, for the 'flag' command and 'server.flag[...]' tags.
      */
     public static SavableMapFlagTracker serverFlagMap;
 
     /**
-     * Last time (System.currentTimeMillis) that scripts wre reloaded.
+     * Last monotonic time (CoreUtilities.monotonicMillis) that scripts wre reloaded.
      */
     public static long lastReloadTime;
 
@@ -81,6 +82,12 @@ public class DenizenCore {
      */
     public static long currentTimeMillis = System.currentTimeMillis();
 
+    /**
+     * Current monotonic time (System.nanoTime), updated per-tick.
+     * Used to avoid multiple checks in the same tick having different time values.
+     */
+    public static long currentTimeMonotonicMillis = CoreUtilities.monotonicMillis();
+
     /**
      * Duration of time, in milliseconds, since the server started.
      */
@@ -128,6 +135,7 @@ public class DenizenCore {
      */
     public static void init(DenizenImplementation implementation) {
         currentTimeMillis = System.currentTimeMillis();
+        currentTimeMonotonicMillis = CoreUtilities.monotonicMillis();
         DenizenCore.implementation = implementation;
         MAIN_THREAD = Thread.currentThread();
         Debug.log("Initializing Denizen Core v" + VERSION +
@@ -194,7 +202,7 @@ public static void postLoadScripts() {
             OldEventManager.scanWorldEvents();
             ScriptEvent.reload();
             implementation.onScriptReload();
-            lastReloadTime = System.currentTimeMillis();
+            lastReloadTime = CoreUtilities.monotonicMillis();
         }
         catch (Exception ex) {
             implementation.debugMessage("Error loading scripts:");
@@ -243,6 +251,7 @@ static void oncePerSecond() {
     public static void tick(int ms_elapsed) {
         serverTimeMillis += ms_elapsed;
         currentTimeMillis = System.currentTimeMillis();
+        currentTimeMonotonicMillis = CoreUtilities.monotonicMillis();
         TickScriptEvent.instance.ticks++;
         if (TickScriptEvent.instance.enabled) {
             TickScriptEvent.instance.fire();

diff --git a/src/main/java/com/denizenscript/denizencore/objects/core/QueueTag.java b/src/main/java/com/denizenscript/denizencore/objects/core/QueueTag.java
@@ -181,11 +181,11 @@ public static void registerTags() {
         // Returns the time this queue started as a duration.
         // -->
         tagProcessor.registerTag(TimeTag.class, "started_time", (attribute, object) -> {
-            return new TimeTag(object.getQueue().startTimeMilli);
+            return new TimeTag(CoreUtilities.monotonicMillisToReal(object.getQueue().startTimeMilli));
         });
         tagProcessor.registerTag(DurationTag.class, "start_time", (attribute, object) -> {
             Deprecations.timeTagRewrite.warn(attribute.context);
-            return new DurationTag(object.getQueue().startTimeMilli / 50);
+            return new DurationTag(CoreUtilities.monotonicMillisToReal(object.getQueue().startTimeMilli) / 50);
         });
 
         // <--[tag]

diff --git a/src/main/java/com/denizenscript/denizencore/objects/core/TimeTag.java b/src/main/java/com/denizenscript/denizencore/objects/core/TimeTag.java
@@ -48,7 +48,7 @@ public class TimeTag implements ObjectTag, Adjustable, FlaggableObject {
     // -->
 
     public static TimeTag now() {
-        return new TimeTag(ZonedDateTime.now());
+        return new TimeTag(DenizenCore.currentTimeMillis, ZoneId.systemDefault());
     }
 
     @Fetchable("time")

diff --git a/src/main/java/com/denizenscript/denizencore/scripts/commands/core/WebGetCommand.java b/src/main/java/com/denizenscript/denizencore/scripts/commands/core/WebGetCommand.java
@@ -242,7 +242,7 @@ public void webGet(final ScriptEntry scriptEntry, final ElementTag data, Element
         BufferedReader buffIn = null;
         HttpURLConnection uc = null;
         try {
-            long timeStart = System.currentTimeMillis();
+            long timeStart = CoreUtilities.monotonicMillis();
             URL url = new URL(urlText.replace(" ", "%20"));
             uc = (HttpURLConnection) url.openConnection();
             uc.setDoInput(true);
@@ -292,7 +292,7 @@ else if (data != null) {
                 }
                 resultHeaders.putObject(key, new ListTag(header.getValue()));
             }
-            final long timeDone = System.currentTimeMillis();
+            final long timeDone = CoreUtilities.monotonicMillis();
             DenizenCore.schedule(new Schedulable() {
                 @Override
                 public boolean tick(float seconds) {

diff --git a/src/main/java/com/denizenscript/denizencore/scripts/commands/queue/WaitCommand.java b/src/main/java/com/denizenscript/denizencore/scripts/commands/queue/WaitCommand.java
@@ -4,6 +4,7 @@
 import com.denizenscript.denizencore.objects.Argument;
 import com.denizenscript.denizencore.objects.core.QueueTag;
 import com.denizenscript.denizencore.scripts.queues.core.TimedQueue;
+import com.denizenscript.denizencore.utilities.CoreUtilities;
 import com.denizenscript.denizencore.utilities.debugging.Debug;
 import com.denizenscript.denizencore.objects.core.DurationTag;
 import com.denizenscript.denizencore.scripts.ScriptEntry;
@@ -69,12 +70,12 @@ public static class SystemTimeDelayTracker implements TimedQueue.DelayTracker {
         public long systemTimeEnd;
 
         public SystemTimeDelayTracker(long millis) {
-            systemTimeEnd = System.currentTimeMillis() + millis;
+            systemTimeEnd = CoreUtilities.monotonicMillis() + millis;
         }
 
         @Override
         public boolean isDelayed() {
-            return systemTimeEnd > System.currentTimeMillis();
+            return systemTimeEnd > CoreUtilities.monotonicMillis();
         }
     }
 

diff --git a/src/main/java/com/denizenscript/denizencore/scripts/commands/queue/WhileCommand.java b/src/main/java/com/denizenscript/denizencore/scripts/commands/queue/WhileCommand.java
@@ -158,7 +158,7 @@ else if (callback != null && callback.asBoolean()) {
                     scriptEntry.getBracedSet().get(0).value.get(scriptEntry.getBracedSet().get(0).value.size() - 1) != scriptEntry)) {
                 WhileData data = (WhileData) scriptEntry.getOwner().getData();
                 data.index++;
-                if (System.currentTimeMillis() - data.LastChecked < 50) {
+                if (CoreUtilities.monotonicMillis() - data.LastChecked < 50) {
                     data.instaTicks++;
                     if (data.instaTicks > CoreConfiguration.whileMaxLoops && CoreConfiguration.whileMaxLoops != 0) {
                         return;
@@ -167,7 +167,7 @@ else if (callback != null && callback.asBoolean()) {
                 else {
                     data.instaTicks = 0;
                 }
-                data.LastChecked = System.currentTimeMillis();
+                data.LastChecked = CoreUtilities.monotonicMillis();
                 boolean run = new IfCommand.ArgComparer().compare(new ArrayList(data.value), scriptEntry);
                 if (run) {
                     if (scriptEntry.dbCallShouldDebug()) {
@@ -207,7 +207,7 @@ else if (callback != null && callback.asBoolean()) {
             WhileData datum = new WhileData();
             datum.index = 1;
             datum.value = comparisons;
-            datum.LastChecked = System.currentTimeMillis();
+            datum.LastChecked = CoreUtilities.monotonicMillis();
             datum.instaTicks = 1;
             scriptEntry.setData(datum);
             ScriptEntry callbackEntry = new ScriptEntry("WHILE", new String[] {"\0CALLBACK"},

diff --git a/src/main/java/com/denizenscript/denizencore/scripts/queues/ScriptQueue.java b/src/main/java/com/denizenscript/denizencore/scripts/queues/ScriptQueue.java
@@ -323,7 +323,7 @@ public final void start(boolean doBasicConfig) {
         if (doBasicConfig) {
             script = script_entries.get(0).getScript();
             startTime = System.nanoTime();
-            startTimeMilli = System.currentTimeMillis();
+            startTimeMilli = CoreUtilities.monotonicMillis();
         }
         String name = getName();
         if (queueNeedsToDebug()) {

diff --git a/src/main/java/com/denizenscript/denizencore/tags/core/UtilTagBase.java b/src/main/java/com/denizenscript/denizencore/tags/core/UtilTagBase.java
@@ -435,6 +435,8 @@ else if (attribute.matches("time_at") && attribute.hasParam()) {
         // @returns TimeTag
         // @description
         // Returns the current system date/time.
+        // This value may be wrong if a server is currently heavily lagging, as it only updates once each tick.
+        // Use <@link tag server.current_time_millis> if you need sub-tick precision.
         // -->
         else if (attribute.startsWith("time_now")) {
             event.setReplacedObject(TimeTag.now().getObjectAttribute(attribute.fulfill(1)));

diff --git a/src/main/java/com/denizenscript/denizencore/utilities/CoreUtilities.java b/src/main/java/com/denizenscript/denizencore/utilities/CoreUtilities.java
@@ -898,4 +898,12 @@ else if (list instanceof ListTag) {
             return ListTag.valueOf(raw, context).objectForms;
         }
     }
+
+    public static long monotonicMillis() {
+        return System.nanoTime() / 1000000;
+    }
+
+    public static long monotonicMillisToReal(long monotonic) {
+        return System.currentTimeMillis() + (monotonic - monotonicMillis());
+    }
 }
diff --git a/src/main/java/com/denizenscript/denizencore/utilities/debugging/SlowWarning.java b/src/main/java/com/denizenscript/denizencore/utilities/debugging/SlowWarning.java
@@ -1,6 +1,7 @@
 package com.denizenscript.denizencore.utilities.debugging;
 
 import com.denizenscript.denizencore.utilities.CoreConfiguration;
+import com.denizenscript.denizencore.utilities.CoreUtilities;
 
 public class SlowWarning extends Warning {
 
@@ -12,7 +13,7 @@ public SlowWarning(String message) {
 
     @Override
     public boolean testShouldWarn() {
-        long cTime = System.currentTimeMillis();
+        long cTime = CoreUtilities.monotonicMillis();
         if (lastWarning + CoreConfiguration.deprecationWarningRate > cTime) {
             return false;
         }