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Improve performance of Iceberg snapshot expiration #13399

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Merged
electrum merged 1 commit into from
Jul 29, 2022
Merged

Improve performance of Iceberg snapshot expiration #13399

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44 changes: 4 additions & 40 deletions plugin/trino-iceberg/src/main/java/io/trino/plugin/iceberg/IcebergMetadata.java
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Original file line number Diff line number Diff line change
Expand Up @@ -20,7 +20,6 @@
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.collect.Sets;
import io.airlift.json.JsonCodec;
import io.airlift.log.Logger;
import io.airlift.slice.Slice;
Expand Down Expand Up @@ -1123,7 +1122,10 @@ private void executeExpireSnapshots(ConnectorSession session, IcebergTableExecut
IcebergSessionProperties.EXPIRE_SNAPSHOTS_MIN_RETENTION);

long expireTimestampMillis = session.getStart().toEpochMilli() - retention.toMillis();
expireSnapshots(table, expireTimestampMillis, session, executeHandle.getSchemaTableName());

table.expireSnapshots()
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@homar homar Jul 29, 2022

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So actually I did it the same way originally but then I got this comment from @rdblue
#10810 (comment)

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@homar homar Jul 29, 2022

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current implementation is based on iceberg's spark extention expire_snapshots

.expireOlderThan(expireTimestampMillis)
.commit();
}

private static void validateTableExecuteParameters(
Expand Down Expand Up @@ -1163,44 +1165,6 @@ private static void validateTableExecuteParameters(
sessionMinRetentionParameterName);
}

private void expireSnapshots(Table table, long expireTimestamp, ConnectorSession session, SchemaTableName schemaTableName)
{
Set<String> originalFiles = buildSetOfValidFiles(table);
table.expireSnapshots().expireOlderThan(expireTimestamp).cleanExpiredFiles(false).commit();
Set<String> validFiles = buildSetOfValidFiles(table);
try {
FileSystem fileSystem = hdfsEnvironment.getFileSystem(new HdfsEnvironment.HdfsContext(session), new Path(table.location()));
Sets.SetView<String> filesToDelete = difference(originalFiles, validFiles);
for (String filePath : filesToDelete) {
log.debug("Deleting file %s while expiring snapshots %s", filePath, schemaTableName.getTableName());
fileSystem.delete(new Path(filePath), false);
}
}
catch (IOException e) {
throw new TrinoException(ICEBERG_FILESYSTEM_ERROR, "Failed accessing data for table: " + schemaTableName, e);
}
}

private static Set<String> buildSetOfValidFiles(Table table)
{
List<Snapshot> snapshots = ImmutableList.copyOf(table.snapshots());
Stream<String> dataFiles = snapshots.stream()
.map(Snapshot::snapshotId)
.flatMap(snapshotId -> stream(table.newScan().useSnapshot(snapshotId).planFiles()))
.map(fileScanTask -> fileScanTask.file().path().toString());
Stream<String> manifests = snapshots.stream()
.flatMap(snapshot -> snapshot.allManifests().stream())
.map(ManifestFile::path);
Stream<String> manifestLists = snapshots.stream()
.map(Snapshot::manifestListLocation);
Stream<String> otherMetadataFiles = concat(
metadataFileLocations(table, false).stream(),
Stream.of(versionHintLocation(table)));
return concat(dataFiles, manifests, manifestLists, otherMetadataFiles)
.map(file -> URI.create(file).getPath())
.collect(toImmutableSet());
}

public void executeRemoveOrphanFiles(ConnectorSession session, IcebergTableExecuteHandle executeHandle)
{
IcebergRemoveOrphanFilesHandle removeOrphanFilesHandle = (IcebergRemoveOrphanFilesHandle) executeHandle.getProcedureHandle();
Expand Down