diff --git a/core/src/main/java/org/apache/druid/java/util/common/FileUtils.java b/core/src/main/java/org/apache/druid/java/util/common/FileUtils.java
index 17f0ed01c33..6025ad6cf73 100644
--- a/core/src/main/java/org/apache/druid/java/util/common/FileUtils.java
+++ b/core/src/main/java/org/apache/druid/java/util/common/FileUtils.java
@@ -242,6 +242,14 @@ public class FileUtils
   {
     return new FilterOutputStream(out)
     {
+      // Default implementation of this method in FilterOutputStream converts single write operation to
+      // multiple write operations of 1 byte each, which is terribly inefficient.
+      @Override
+      public void write(byte b[], int off, int len) throws IOException
+      {
+        out.write(b, off, len);
+      }
+
       @Override
       public void close()
       {