Make Commitlog flush data safely in Direct IO mode

Maxwell-Guo · Maxwell-Guo · commit 8de4c9250eeb · 2025-06-17T23:24:06.000+08:00
patch by Maxwell Guo; reviewed by Ariel Weisberg for CASSANDRA-20692
diff --git a/CHANGES.txt b/CHANGES.txt
@@ -1,4 +1,5 @@
 5.0.5
+ * Make Commitlog flush data safely in Direct IO mode (CASSANDRA-20692)
  * Get SAI MemtableIndex refs before SSTableIndex refs at query time (CASSANDRA-20709)
  * Fix MAX_SEGMENT_SIZE < chunkSize in MmappedRegions::updateState (CASSANDRA-20636)
  * Full Java 17 support (CASSANDRA-20681)
diff --git a/src/java/org/apache/cassandra/db/commitlog/DirectIOSegment.java b/src/java/org/apache/cassandra/db/commitlog/DirectIOSegment.java
@@ -177,7 +177,12 @@ public DirectIOSegmentBuilder(AbstractCommitLogSegmentManager segmentManager, in
         public DirectIOSegment build()
         {
             return new DirectIOSegment(segmentManager,
-                                       path -> FileChannel.open(path, StandardOpenOption.WRITE, StandardOpenOption.READ, StandardOpenOption.CREATE, ExtendedOpenOption.DIRECT),
+                                       path -> FileChannel.open(path,
+                                                                StandardOpenOption.WRITE,
+                                                                StandardOpenOption.READ,
+                                                                StandardOpenOption.CREATE,
+                                                                StandardOpenOption.DSYNC,
+                                                                ExtendedOpenOption.DIRECT),
                                        fsBlockSize);
         }
 

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,5 @@`
`1`	`1`	`5.0.5`
	`2`	`+ * Make Commitlog flush data safely in Direct IO mode (CASSANDRA-20692)`
`2`	`3`	`* Get SAI MemtableIndex refs before SSTableIndex refs at query time (CASSANDRA-20709)`
`3`	`4`	`* Fix MAX_SEGMENT_SIZE < chunkSize in MmappedRegions::updateState (CASSANDRA-20636)`
`4`	`5`	`* Full Java 17 support (CASSANDRA-20681)`
Original file line number	Diff line number	Diff line change
`@@ -177,7 +177,12 @@ public DirectIOSegmentBuilder(AbstractCommitLogSegmentManager segmentManager, in`
`177`	`177`	`public DirectIOSegment build()`
`178`	`178`	`{`
`179`	`179`	`return new DirectIOSegment(segmentManager,`
`180`		`- path -> FileChannel.open(path, StandardOpenOption.WRITE, StandardOpenOption.READ, StandardOpenOption.CREATE, ExtendedOpenOption.DIRECT),`
	`180`	`+ path -> FileChannel.open(path,`
	`181`	`+ StandardOpenOption.WRITE,`
	`182`	`+ StandardOpenOption.READ,`
	`183`	`+ StandardOpenOption.CREATE,`
	`184`	`+ StandardOpenOption.DSYNC,`
	`185`	`+ ExtendedOpenOption.DIRECT),`
`181`	`186`	`fsBlockSize);`
`182`	`187`	`}`
`183`	`188`