HDFS-16082. Atomic operations on exceptionsSinceLastBalance and failedTimesSinceLastSuccessfulBalance in Balancer (#3127)
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/balancer/Balancer.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/balancer/Balancer.java
index 33650ea..73a8e68 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/balancer/Balancer.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/balancer/Balancer.java
@@ -37,6 +37,7 @@
import java.util.Map;
import java.util.Set;
import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
import org.apache.commons.lang3.builder.ToStringBuilder;
import org.apache.hadoop.thirdparty.com.google.common.annotations.VisibleForTesting;
@@ -211,8 +212,10 @@
@VisibleForTesting
private static volatile boolean serviceRunning = false;
- private static volatile int exceptionsSinceLastBalance = 0;
- private static volatile int failedTimesSinceLastSuccessfulBalance = 0;
+ private static final AtomicInteger EXCEPTIONS_SINCE_LAST_BALANCE =
+ new AtomicInteger(0);
+ private static final AtomicInteger
+ FAILED_TIMES_SINCE_LAST_SUCCESSFUL_BALANCE = new AtomicInteger(0);
private final Dispatcher dispatcher;
private final NameNodeConnector nnc;
@@ -274,11 +277,11 @@
}
static int getExceptionsSinceLastBalance() {
- return exceptionsSinceLastBalance;
+ return EXCEPTIONS_SINCE_LAST_BALANCE.get();
}
static int getFailedTimesSinceLastSuccessfulBalance() {
- return failedTimesSinceLastSuccessfulBalance;
+ return FAILED_TIMES_SINCE_LAST_SUCCESSFUL_BALANCE.get();
}
/**
@@ -866,20 +869,21 @@
int retCode = doBalance(namenodes, nsIds, p, conf);
if (retCode < 0) {
LOG.info("Balance failed, error code: " + retCode);
- failedTimesSinceLastSuccessfulBalance++;
+ FAILED_TIMES_SINCE_LAST_SUCCESSFUL_BALANCE.incrementAndGet();
} else {
LOG.info("Balance succeed!");
- failedTimesSinceLastSuccessfulBalance = 0;
+ FAILED_TIMES_SINCE_LAST_SUCCESSFUL_BALANCE.set(0);
}
- exceptionsSinceLastBalance = 0;
+ EXCEPTIONS_SINCE_LAST_BALANCE.set(0);
} catch (Exception e) {
- if (++exceptionsSinceLastBalance > retryOnException) {
+ if (EXCEPTIONS_SINCE_LAST_BALANCE.incrementAndGet()
+ > retryOnException) {
// The caller will process and log the exception
throw e;
}
LOG.warn(
"Encounter exception while do balance work. Already tried {} times",
- exceptionsSinceLastBalance, e);
+ EXCEPTIONS_SINCE_LAST_BALANCE, e);
}
// sleep for next round, will retry for next round when it's interrupted
