From 3845790c5d24ea69b1724acd45fdf27a76321c0c Mon Sep 17 00:00:00 2001
From: Greg Wilkins <gregw@webtide.com>
Date: Wed, 20 May 2020 10:47:23 +0200
Subject: [PATCH] Hpack optimizations

If the dynamic table size is already 0, do not evictAll.

Signed-off-by: Greg Wilkins <gregw@webtide.com>
---
 .../eclipse/jetty/http2/hpack/HpackContext.java   | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/jetty-http2/http2-hpack/src/main/java/org/eclipse/jetty/http2/hpack/HpackContext.java b/jetty-http2/http2-hpack/src/main/java/org/eclipse/jetty/http2/hpack/HpackContext.java
index ab587240876..5625b2c0cb9 100644
--- a/jetty-http2/http2-hpack/src/main/java/org/eclipse/jetty/http2/hpack/HpackContext.java
+++ b/jetty-http2/http2-hpack/src/main/java/org/eclipse/jetty/http2/hpack/HpackContext.java
@@ -395,12 +395,15 @@ public class HpackContext
         {
             if (LOG.isDebugEnabled())
                 LOG.debug(String.format("HdrTbl[%x] evictAll", HpackContext.this.hashCode()));
-            _fieldMap.clear();
-            _nameMap.clear();
-            _offset = 0;
-            _size = 0;
-            _dynamicTableSizeInBytes = 0;
-            Arrays.fill(_entries, null);
+            if (size() > 0)
+            {
+                _fieldMap.clear();
+                _nameMap.clear();
+                _offset = 0;
+                _size = 0;
+                _dynamicTableSizeInBytes = 0;
+                Arrays.fill(_entries, null);
+            }
         }
     }