Ensure thread ratio calc is valid

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@830589 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/java/org/apache/coyote/http11/Http11Processor.java b/java/org/apache/coyote/http11/Http11Processor.java
index a69304e..48137dd 100644 (file)
--- a/java/org/apache/coyote/http11/Http11Processor.java
+++ b/java/org/apache/coyote/http11/Http11Processor.java
@@ -171,8 +171,16 @@ public class Http11Processor extends AbstractHttp11Processor implements ActionHo
         
         int soTimeout = endpoint.getSoTimeout();
 
-        int threadRatio = (endpoint.getCurrentThreadsBusy() * 100)
-                / endpoint.getMaxThreads();
+        int threadRatio = -1;
+        // These may return zero or negative values
+        // Only calculate a thread ratio when both are >0 to ensure we get a
+        // sensible result
+        if (endpoint.getCurrentThreadsBusy() >0 &&
+                endpoint.getMaxThreads() >0) {
+            threadRatio = (endpoint.getCurrentThreadsBusy() * 100)
+                    / endpoint.getMaxThreads();
+        }
+        // Disable keep-alive if we are running low on threads
         if (threadRatio > 75) {
             keepAliveLeft = 1;
         }