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Posted to issues@ozone.apache.org by "Tejaskriya (via GitHub)" <gi...@apache.org> on 2025/08/04 07:10:21 UTC
[PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Tejaskriya opened a new pull request, #8893:
URL: https://github.com/apache/ozone/pull/8893
## What changes were proposed in this pull request?
This PR adds container scans in the following cases:
- EC reconstruction: during success
- Reconciler: for success and failure
- Export container: for failure
And volume scan is triggered during the following cases:
- Import container : during failure
## What is the link to the Apache JIRA
https://issues.apache.org/jira/browse/HDDS-13238
## How was this patch tested?
Added unit tests
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "errose28 (via GitHub)" <gi...@apache.org>.
errose28 commented on code in PR #8893:
URL: https://github.com/apache/ozone/pull/8893#discussion_r2277693421
##########
hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/keyvalue/KeyValueHandler.java:
##########
@@ -1564,6 +1564,19 @@ public void deleteContainer(Container container, boolean force)
@Override
public void reconcileContainer(DNContainerOperationClient dnClient, Container<?> container,
Collection<DatanodeDetails> peers) throws IOException {
+ long containerID = container.getContainerData().getContainerID();
+ try {
+ reconcileContainerInternal(dnClient, container, peers);
+ } finally {
+ // Trigger on demand scanner, which will build the merkle tree based on the newly ingested data.
+ containerSet.scanContainerWithoutGap(containerID,
+ "Container reconciliation");
+ sendICR(container);
Review Comment:
We can leave `sendICR` at the end of `reconcileContainerInternal`. There is no ordering between these two operations since the scan is async. The initial ICR gives SCM the potentially updated container checksum after reconciliation based only on the metadata ingested. The on-demand scan afterwards will send another one if it finds that the data actually has a different checksum than the one computed from the metadata.
The current version sends an ICR even if reconcile throws an exception before making a modification to the container. In this case we should let the scanner see what's wrong and decide if an ICR is necessary.
##########
hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/ec/reconstruction/ECReconstructionCoordinator.java:
##########
@@ -189,6 +189,8 @@ public void reconstructECContainerGroup(long containerID,
}
metrics.incReconstructionTotal();
metrics.incBlockGroupReconstructionTotal(blockLocationInfoMap.size());
+ // Trigger a container scan after successful reconstruction
+ context.getParent().getContainer().getContainerSet().scanContainer(containerID, "EC reconstruction");
Review Comment:
The coordinator is not always creating replicas locally. It can also pull data from other replicas, create missing chunks, and push those to other nodes. At the end of reconstruction it calls [closeContainer](https://github.com/apache/ozone/blob/9553660a9dadefe6accd85a12af84f9bca5fe3cf/hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/ec/reconstruction/ECReconstructionCoordinator.java#L188) on any peers that were under reconstruction, so we need to put the scan on the receiving end of this call.
The flow looks to be that the container goes `RECOVERING -> CLOSING -> CLOSED`, but the `closing -> closed` transition happens at the same time in [handleCloseContainer](https://github.com/apache/ozone/blob/9553660a9dadefe6accd85a12af84f9bca5fe3cf/hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/keyvalue/KeyValueHandler.java#L598). Since we can't scan `CLOSING` containers, we probably need something like this in `KeyValueHandler#handleCloseContainer`:
- Save the container's start state at the top of the method
- Let the closing and close calls within the method complete
- Then check if the start we saved was `RECOVERING`, trigger an on-demand scan on the noew closed container.
This should be unit testable in `TestKeyValueHandler`.
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "Tejaskriya (via GitHub)" <gi...@apache.org>.
Tejaskriya commented on code in PR #8893:
URL: https://github.com/apache/ozone/pull/8893#discussion_r2291156052
##########
hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/hdds/scm/storage/TestContainerCommandsEC.java:
##########
Review Comment:
It isn't necessary, I have removed these changes now, Thanks!
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "errose28 (via GitHub)" <gi...@apache.org>.
errose28 commented on code in PR #8893:
URL: https://github.com/apache/ozone/pull/8893#discussion_r2285991128
##########
hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/keyvalue/KeyValueHandler.java:
##########
@@ -607,8 +607,13 @@ ContainerCommandResponseProto handleCloseContainer(
return malformedRequest(request);
}
try {
+ ContainerProtos.ContainerDataProto.State currentState = kvContainer.getContainerState();
markContainerForClose(kvContainer);
closeContainer(kvContainer);
+ if (currentState == RECOVERING) {
+ // trigger container scan for recovering containers, i.e., after EC reconstruction
+ containerSet.scanContainer(kvContainer.getContainerData().getContainerID(), "EC Reconstruction");
+ }
Review Comment:
Just a minor name/comment change to reflect the state of the container at the time we are checking it.
```suggestion
ContainerProtos.ContainerDataProto.State previousState = kvContainer.getContainerState();
markContainerForClose(kvContainer);
closeContainer(kvContainer);
if (previousState == RECOVERING) {
// trigger container scan for recovered containers after EC reconstruction
containerSet.scanContainer(kvContainer.getContainerData().getContainerID(), "EC Reconstruction");
}
```
##########
hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/keyvalue/TestKeyValueHandler.java:
##########
@@ -392,6 +393,45 @@ public void testCloseInvalidContainer(ContainerLayoutVersion layoutVersion)
"Close container should return Invalid container error");
}
+ @ContainerLayoutTestInfo.ContainerTest
+ public void testCloseRecoveringContainerTriggersScan(ContainerLayoutVersion layoutVersion) {
+ final ContainerSet containerSet = spy(newContainerSet());
Review Comment:
We don't need a new spy here. There's a `mockContainerSet` field in this test already. The test still passes when we use that.
##########
hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/keyvalue/TestKeyValueHandler.java:
##########
@@ -392,6 +393,45 @@ public void testCloseInvalidContainer(ContainerLayoutVersion layoutVersion)
"Close container should return Invalid container error");
}
+ @ContainerLayoutTestInfo.ContainerTest
+ public void testCloseRecoveringContainerTriggersScan(ContainerLayoutVersion layoutVersion) {
+ final ContainerSet containerSet = spy(newContainerSet());
+ final KeyValueHandler keyValueHandler = new KeyValueHandler(conf,
+ DATANODE_UUID, containerSet, mock(MutableVolumeSet.class), mock(ContainerMetrics.class),
+ c -> { }, new ContainerChecksumTreeManager(conf));
+
+ conf = new OzoneConfiguration();
+ KeyValueContainerData kvData = new KeyValueContainerData(DUMMY_CONTAINER_ID,
+ layoutVersion,
+ (long) StorageUnit.GB.toBytes(1), UUID.randomUUID().toString(),
+ UUID.randomUUID().toString());
+ kvData.setMetadataPath(tempDir.toString());
+ kvData.setDbFile(dbFile.toFile());
+ KeyValueContainer container = new KeyValueContainer(kvData, conf);
+ ContainerCommandRequestProto createContainerRequest =
+ createContainerRequest(DATANODE_UUID, DUMMY_CONTAINER_ID);
+ keyValueHandler.handleCreateContainer(createContainerRequest, container);
+
+ // Make the container state as invalid.
+ kvData.setState(State.RECOVERING);
+
+ // Create Close container request
+ ContainerCommandRequestProto closeContainerRequest =
+ ContainerProtos.ContainerCommandRequestProto.newBuilder()
+ .setCmdType(ContainerProtos.Type.CloseContainer)
+ .setContainerID(DUMMY_CONTAINER_ID)
+ .setDatanodeUuid(DATANODE_UUID)
+ .setCloseContainer(ContainerProtos.CloseContainerRequestProto
+ .getDefaultInstance())
+ .build();
+ dispatcher.dispatch(closeContainerRequest, null);
+
+ keyValueHandler.handleCloseContainer(closeContainerRequest, container);
+
+ verify(keyValueHandler.getContainerSet(), atLeastOnce())
+ .scanContainer(DUMMY_CONTAINER_ID, "EC Reconstruction");
Review Comment:
This should do the same thing but we can get rid of the testing getter in `Handler`.
```suggestion
verify(containerSet, atLeastOnce()).scanContainer(DUMMY_CONTAINER_ID, "EC Reconstruction");
```
##########
hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/hdds/scm/storage/TestContainerCommandsEC.java:
##########
Review Comment:
Are changes to this file still necessary now that the EC reconstruction coordinator is not changing?
##########
hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/keyvalue/TestContainerReconciliationWithMockDatanodes.java:
##########
@@ -305,6 +310,30 @@ public void testContainerReconciliationWithPeerFailure(FailureLocation failureLo
mockContainerProtocolCalls();
}
+ @Test
+ public void testContainerReconciliationFailureContainerScan()
+ throws Exception {
+ // Use synchronous on-demand scans to re-build the merkle trees after corruption.
+ datanodes.forEach(d -> d.scanContainer(CONTAINER_ID));
+
+ // Each datanode should have had one on-demand scan during test setup, and a second one after corruption was
+ // introduced.
+ waitForExpectedScanCount(1);
+
+ for (MockDatanode current : datanodes) {
+ doThrow(IOException.class).when(current.getHandler().getChecksumManager()).read(any());
+ List<DatanodeDetails> peers = datanodes.stream()
+ .map(MockDatanode::getDnDetails)
+ .filter(other -> !current.getDnDetails().equals(other))
+ .collect(Collectors.toList());
+ // Reconciliation should fail for each datanode, since the checksum info cannot be retrieved.
+ assertThrows(IOException.class, () -> current.reconcileContainer(dnClient, peers, CONTAINER_ID));
+ Mockito.reset(current.getHandler().getChecksumManager());
+ }
+ // Even failure of Reconciliation should have triggered a second on-demand scan for each replica.
+ waitForExpectedScanCount(2);
+ }
Review Comment:
This version of the test also passes, but does not require extra changes to accommodate the spy.
```suggestion
@Test
public void testContainerReconciliationFailureContainerScan() throws Exception {
for (MockDatanode current : datanodes) {
List<DatanodeDetails> peers = datanodes.stream()
.map(MockDatanode::getDnDetails)
.filter(other -> !current.getDnDetails().equals(other))
.collect(Collectors.toList());
FileUtils.deleteDirectory(new File(current.getContainer(CONTAINER_ID).getContainerData().getMetadataPath()));
// Reconciliation should fail without a metadata directory present.
assertThrows(IOException.class, () -> current.reconcileContainer(dnClient, peers, CONTAINER_ID));
Mockito.reset(current.getHandler().getChecksumManager());
}
// Each replica should have an on-demand scan triggered when reconciliation failed.
waitForExpectedScanCount(1);
datanodes.forEach(d -> assertTrue(d.getContainer(CONTAINER_ID).getContainerData().isUnhealthy()));
}
```
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "adoroszlai (via GitHub)" <gi...@apache.org>.
adoroszlai commented on code in PR #8893:
URL: https://github.com/apache/ozone/pull/8893#discussion_r2253888752
##########
hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/keyvalue/KeyValueHandler.java:
##########
Review Comment:
- For reviewers: "Real" change can be viewed with `git diff --ignore-space-change`
- @Tejaskriya You can reduce change in such case by extracting code to a private method and calling it from the `try` block. This will keep indent of the extracted code at the same level.
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "Tejaskriya (via GitHub)" <gi...@apache.org>.
Tejaskriya commented on code in PR #8893:
URL: https://github.com/apache/ozone/pull/8893#discussion_r2253845283
##########
hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/keyvalue/KeyValueHandler.java:
##########
Review Comment:
A note for reviewers:
The changes in this file is to simply surround the major code of `reconcileContainer` with a try block, and move the scan trigger and sending ICR to a finally block
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "Tejaskriya (via GitHub)" <gi...@apache.org>.
Tejaskriya commented on code in PR #8893:
URL: https://github.com/apache/ozone/pull/8893#discussion_r2291166409
##########
hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/keyvalue/TestContainerReconciliationWithMockDatanodes.java:
##########
@@ -305,6 +310,30 @@ public void testContainerReconciliationWithPeerFailure(FailureLocation failureLo
mockContainerProtocolCalls();
}
+ @Test
+ public void testContainerReconciliationFailureContainerScan()
+ throws Exception {
+ // Use synchronous on-demand scans to re-build the merkle trees after corruption.
+ datanodes.forEach(d -> d.scanContainer(CONTAINER_ID));
+
+ // Each datanode should have had one on-demand scan during test setup, and a second one after corruption was
+ // introduced.
+ waitForExpectedScanCount(1);
+
+ for (MockDatanode current : datanodes) {
+ doThrow(IOException.class).when(current.getHandler().getChecksumManager()).read(any());
+ List<DatanodeDetails> peers = datanodes.stream()
+ .map(MockDatanode::getDnDetails)
+ .filter(other -> !current.getDnDetails().equals(other))
+ .collect(Collectors.toList());
+ // Reconciliation should fail for each datanode, since the checksum info cannot be retrieved.
+ assertThrows(IOException.class, () -> current.reconcileContainer(dnClient, peers, CONTAINER_ID));
+ Mockito.reset(current.getHandler().getChecksumManager());
+ }
+ // Even failure of Reconciliation should have triggered a second on-demand scan for each replica.
+ waitForExpectedScanCount(2);
+ }
Review Comment:
This version of the test seems to be failing, and it causes the other test for peers to fail too (I think they are all sharing the same set of containers so the deletion affects both). The IOException isn't thrown when we do this
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "Tejaskriya (via GitHub)" <gi...@apache.org>.
Tejaskriya commented on code in PR #8893:
URL: https://github.com/apache/ozone/pull/8893#discussion_r2253909528
##########
hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/keyvalue/KeyValueHandler.java:
##########
Review Comment:
Oh I was not aware of that, I'll take up your suggestion. Will open it for reviews after these changes. Thank you!
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "errose28 (via GitHub)" <gi...@apache.org>.
errose28 commented on PR #8893:
URL: https://github.com/apache/ozone/pull/8893#issuecomment-3165501589
In this PR, let's also update [this location](https://github.com/apache/ozone/blob/3c4b3bec36e7f8c8b2bb4793d2e1088b60fc148f/hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/keyvalue/KeyValueContainer.java#L314) which gets triggered when the container file cannot be updated. We should do an on-demand container scan first, and only a volume scan if that fails. However, we don't want to trigger the on-demand container scan in this exact spot in case this is being called to mark the container unhealthy, or it will get stuck in a loop. Instead we probably want to trigger it [here](https://github.com/apache/ozone/blob/3c4b3bec36e7f8c8b2bb4793d2e1088b60fc148f/hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/keyvalue/KeyValueContainer.java#L487).
Note that if a container scan fails due to permission errors, the result will only be kept in memory. Persistence will fail since we don't have permission to update the file, but that is desirable since permissions can be restored on restart. Let's add a comment explaining that in this scan location as well.
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "Tejaskriya (via GitHub)" <gi...@apache.org>.
Tejaskriya commented on PR #8893:
URL: https://github.com/apache/ozone/pull/8893#issuecomment-3195487369
@errose28 I have made the changes as described in your review comments above, please take a look again, thanks!
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "errose28 (via GitHub)" <gi...@apache.org>.
errose28 commented on code in PR #8893:
URL: https://github.com/apache/ozone/pull/8893#discussion_r2291947842
##########
hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/keyvalue/TestContainerReconciliationWithMockDatanodes.java:
##########
@@ -305,6 +310,30 @@ public void testContainerReconciliationWithPeerFailure(FailureLocation failureLo
mockContainerProtocolCalls();
}
+ @Test
+ public void testContainerReconciliationFailureContainerScan()
+ throws Exception {
+ // Use synchronous on-demand scans to re-build the merkle trees after corruption.
+ datanodes.forEach(d -> d.scanContainer(CONTAINER_ID));
+
+ // Each datanode should have had one on-demand scan during test setup, and a second one after corruption was
+ // introduced.
+ waitForExpectedScanCount(1);
+
+ for (MockDatanode current : datanodes) {
+ doThrow(IOException.class).when(current.getHandler().getChecksumManager()).read(any());
+ List<DatanodeDetails> peers = datanodes.stream()
+ .map(MockDatanode::getDnDetails)
+ .filter(other -> !current.getDnDetails().equals(other))
+ .collect(Collectors.toList());
+ // Reconciliation should fail for each datanode, since the checksum info cannot be retrieved.
+ assertThrows(IOException.class, () -> current.reconcileContainer(dnClient, peers, CONTAINER_ID));
+ Mockito.reset(current.getHandler().getChecksumManager());
+ }
+ // Even failure of Reconciliation should have triggered a second on-demand scan for each replica.
+ waitForExpectedScanCount(2);
+ }
Review Comment:
This passes in isolation for me locally, but I forgot this test re-uses container instances across tests to make sure the data is truly repaired. Mocking the fault injection like the current code does is probably the easier approach here.
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Re: [PR] HDDS-13238. Scan container and volume in container import & export, EC reconstruction, reconciliation [ozone]
Posted by "errose28 (via GitHub)" <gi...@apache.org>.
errose28 merged PR #8893:
URL: https://github.com/apache/ozone/pull/8893
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