HDFS-17626. Reduce lock contention at datanode startup (#7053). Contributed by Tao Li.

Signed-off-by: Ayush Saxena <ayushsaxena@apache.org>
Signed-off-by: He Xiaoqiao <hexiaoqiao@apache.org>

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BPServiceActor.java

@@ -258,7 +258,7 @@ class BPServiceActor implements Runnable {
     while (shouldRun()) {
       try {
         nsInfo = bpNamenode.versionRequest();
-        LOG.debug(this + " received versionRequest response: " + nsInfo);
+        LOG.debug("{} received versionRequest response: {}", this, nsInfo);
         break;
       } catch(SocketTimeoutException e) {  // namenode is busy
         LOG.warn("Problem connecting to server: " + nnAddr);