[OAK-8565] Using a lazy blob listing can cause Azure timeout

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.18.0
• Component/s: segment-azure
• Assignee: Tomek Rękawek
• Reporter: Tomek Rękawek
• Created: 21/Aug/19 09:22
• Updated: 30/Sep/19 07:35
• Resolved: 21/Aug/19 09:55

Description

When trying to list the Azure blob in a lazy way, the API client loads the listing in a few segments. If there's too much time between segment requests (eg. because we're processing each blob), it can result in TimeoutException:

[FelixStartLevel] org.apache.jackrabbit.oak-segment-tar bundle org.apache.jackrabbit.oak-segment-tar:1.16.0.R1864511 (144)[org.apache.jackrabbit.oak.segment.SegmentNodeStoreFactory(204)] : The activate method has thrown an exception (java.util.NoSuchElementException: An error occurred while enumerating the result, check the original exception for details.)
java.util.NoSuchElementException: An error occurred while enumerating the result, check the original exception for details.
	at com.microsoft.azure.storage.core.LazySegmentedIterator.hasNext(LazySegmentedIterator.java:113)
	at java.base/java.util.Iterator.forEachRemaining(Iterator.java:132)
	at java.base/java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801)
	at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
	at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
	at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:497)
	at org.apache.jackrabbit.oak.segment.azure.AzureArchiveManager.renameTo(AzureArchiveManager.java:134) [org.apache.jackrabbit.oak-segment-azure:1.16.0.R1864511]
	at org.apache.jackrabbit.oak.segment.file.tar.TarReader.backupSafely(TarReader.java:208) [org.apache.jackrabbit.oak-segment-tar:1.16.0.R1864511]
	at org.apache.jackrabbit.oak.segment.file.tar.TarReader.collectFileEntries(TarReader.java:154) [org.apache.jackrabbit.oak-segment-tar:1.16.0.R1864511]
	at org.apache.jackrabbit.oak.segment.file.tar.TarReader.open(TarReader.java:99) [org.apache.jackrabbit.oak-segment-tar:1.16.0.R1864511]
	at org.apache.jackrabbit.oak.segment.file.tar.TarFiles.<init>(TarFiles.java:395) [org.apache.jackrabbit.oak-segment-tar:1.16.0.R1864511]
...
Caused by: com.microsoft.azure.storage.StorageException: The client could not finish the operation within specified maximum execution timeout.
	at com.microsoft.azure.storage.core.ExecutionEngine.setupStorageRequest(ExecutionEngine.java:277)
	at com.microsoft.azure.storage.core.ExecutionEngine.executeWithRetry(ExecutionEngine.java:95)
	at com.microsoft.azure.storage.core.LazySegmentedIterator.hasNext(LazySegmentedIterator.java:109)
	... 58 common frames omitted
Caused by: java.util.concurrent.TimeoutException: The client could not finish the operation within specified maximum execution timeout.
	at com.microsoft.azure.storage.core.ExecutionEngine.setupStorageRequest(ExecutionEngine.java:276)
	... 60 common frames omitted

We should update the code to load all blobs into a list and return it.