[iotdb] branch rel/0.12 updated: minor improve the concurrency problem (#3036)

[neuyilan]

This is an automated email from the ASF dual-hosted git repository.

neuyilan pushed a commit to branch rel/0.12
in repository https://gitbox.apache.org/repos/asf/iotdb.git


The following commit(s) were added to refs/heads/rel/0.12 by this push:
     new 1e135e5  minor improve the concurrency problem (#3036)
1e135e5 is described below

commit 1e135e5ab8b21cf20b0cf389acf3c0b142837a3b
Author: HouliangQi <neuyi...@163.com>
AuthorDate: Wed Apr 21 10:20:18 2021 +0800

    minor improve the concurrency problem (#3036)
---
 .../org/apache/iotdb/cluster/log/catchup/LogCatchUpTask.java |  4 ++--
 .../iotdb/cluster/log/manage/CommittedEntryManager.java      | 12 +++++++++---
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git 
a/cluster/src/main/java/org/apache/iotdb/cluster/log/catchup/LogCatchUpTask.java
 
b/cluster/src/main/java/org/apache/iotdb/cluster/log/catchup/LogCatchUpTask.java
index e16f99c..dcb287d 100644
--- 
a/cluster/src/main/java/org/apache/iotdb/cluster/log/catchup/LogCatchUpTask.java
+++ 
b/cluster/src/main/java/org/apache/iotdb/cluster/log/catchup/LogCatchUpTask.java
@@ -266,7 +266,7 @@ public class LogCatchUpTask implements Callable<Boolean> {
     }
     // do append entries
     if (logger.isInfoEnabled()) {
-      logger.info("{}: sending {} logs to {}", raftMember.getName(), node, 
logList.size());
+      logger.info("{}: sending {} logs to {}", raftMember.getName(), 
logList.size(), node);
     }
     if (ClusterDescriptor.getInstance().getConfig().isUseAsyncServer()) {
       abort = !appendEntriesAsync(logList, request);
@@ -274,7 +274,7 @@ public class LogCatchUpTask implements Callable<Boolean> {
       abort = !appendEntriesSync(logList, request);
     }
     if (!abort && logger.isInfoEnabled()) {
-      logger.info("{}: sent {} logs to {}", raftMember.getName(), node, 
logList.size());
+      logger.info("{}: sent {} logs to {}", raftMember.getName(), 
logList.size(), node);
     }
     logList.clear();
   }
diff --git 
a/cluster/src/main/java/org/apache/iotdb/cluster/log/manage/CommittedEntryManager.java
 
b/cluster/src/main/java/org/apache/iotdb/cluster/log/manage/CommittedEntryManager.java
index c08334e..e86df85 100644
--- 
a/cluster/src/main/java/org/apache/iotdb/cluster/log/manage/CommittedEntryManager.java
+++ 
b/cluster/src/main/java/org/apache/iotdb/cluster/log/manage/CommittedEntryManager.java
@@ -208,13 +208,19 @@ public class CommittedEntryManager {
       throw new EntryUnavailableException(compactIndex, getLastIndex());
     }
     int index = (int) (compactIndex - dummyIndex);
+    for (int i = 1; i <= index; i++) {
+      entryTotalMemSize -= entries.get(i).getByteSize();
+    }
+    // The following two lines of code should be tightly linked,
+    // because the check apply thread will read the entry also, and there will 
be concurrency
+    // problems,
+    // but please rest assured that we have done concurrency security check in 
the check apply
+    // thread.
+    // They are put together just to reduce the probability of concurrency.
     entries.set(
         0,
         new EmptyContentLog(
             entries.get(index).getCurrLogIndex(), 
entries.get(index).getCurrLogTerm()));
-    for (int i = 1; i <= index; i++) {
-      entryTotalMemSize -= entries.get(i).getByteSize();
-    }
     entries.subList(1, index + 1).clear();
   }