use of io.pravega.common.util.ByteArraySegment in project pravega by pravega.
the class RedirectedReadResultEntryTests method testConstructor.
/**
* Tests the ability of the ReadResultEntry base class to adjust offsets when instructed so.
*/
@Test
public void testConstructor() {
final long originalOffset = 123;
final int originalLength = 321;
final int positiveDelta = 8976;
final int negativeDelta = -76;
val baseEntry = new MockReadResultEntry(originalOffset, originalLength);
AssertExtensions.assertThrows("Constructor allowed changing to a negative offset.", () -> new RedirectedReadResultEntry(baseEntry, -originalOffset - 1, this::illegalGetNext, 2), ex -> ex instanceof IllegalArgumentException);
// Adjust up.
RedirectedReadResultEntry redirectedEntry = new RedirectedReadResultEntry(baseEntry, positiveDelta, this::illegalGetNext, 2);
Assert.assertEquals("Unexpected value for getStreamSegmentOffset after up-adjustment.", originalOffset + positiveDelta, redirectedEntry.getStreamSegmentOffset());
Assert.assertEquals("Unexpected value for getRequestedReadLength after up-adjustment (no change expected).", originalLength, redirectedEntry.getRequestedReadLength());
// Adjust down.
redirectedEntry = new RedirectedReadResultEntry(baseEntry, negativeDelta, this::illegalGetNext, 2);
Assert.assertEquals("Unexpected value for getStreamSegmentOffset after down-adjustment.", originalOffset + negativeDelta, redirectedEntry.getStreamSegmentOffset());
Assert.assertEquals("Unexpected value for getRequestedReadLength after down-adjustment (no change expected).", originalLength, redirectedEntry.getRequestedReadLength());
// Verify other properties are as they should.
Assert.assertEquals("Unexpected value for getType.", baseEntry.getType(), redirectedEntry.getType());
Assert.assertEquals("Unexpected value for getRequestedReadLength.", baseEntry.getRequestedReadLength(), redirectedEntry.getRequestedReadLength());
// getContent will be thoroughly tested in its own unit test.
baseEntry.getContent().complete(new ByteArraySegment(new byte[1]));
Assert.assertEquals("Unexpected result for getContent.", baseEntry.getContent().join(), redirectedEntry.getContent().join());
redirectedEntry.requestContent(Duration.ZERO);
Assert.assertTrue("BaseEntry.getContent() was not completed when requestContent was invoked.", Futures.isSuccessful(baseEntry.getContent()));
}
use of io.pravega.common.util.ByteArraySegment in project pravega by pravega.
the class StreamSegmentReadResultTests method testNextTerminal.
private void testNextTerminal(BiFunction<Long, Integer, TestReadResultEntry> terminalEntryCreator) {
AtomicReference<TestReadResultEntry> nextEntry = new AtomicReference<>();
StreamSegmentReadResult.NextEntrySupplier nes = (offset, length, makeCopy) -> nextEntry.get();
// We issue a read with length = MAX_RESULT_LENGTH, and return only half the items, 1 byte at a time.
@Cleanup StreamSegmentReadResult r = new StreamSegmentReadResult(START_OFFSET, MAX_RESULT_LENGTH, nes, "");
for (int i = 0; i < MAX_RESULT_LENGTH / 2; i++) {
// Setup an item to be returned.
final long expectedStartOffset = START_OFFSET + i;
final int expectedReadLength = MAX_RESULT_LENGTH - i;
nextEntry.set(TestReadResultEntry.cache(expectedStartOffset, expectedReadLength));
r.next();
nextEntry.get().complete(new ByteArraySegment(new byte[READ_ITEM_LENGTH]));
}
// Verify we have not reached the end.
AssertExtensions.assertLessThan("Unexpected state of the StreamSegmentReadResult when consuming half of the result.", r.getMaxResultLength(), r.getConsumedLength());
Assert.assertTrue("hasNext() did not return true when more items are to be consumed.", r.hasNext());
// Next time we call next(), return an End-of-StreamSegment entry.
nextEntry.set(terminalEntryCreator.apply((long) START_OFFSET + MAX_RESULT_LENGTH / 2, MAX_RESULT_LENGTH / 2));
ReadResultEntry resultEntry = r.next();
Assert.assertEquals("Unexpected result from nextEntry() when returning the terminal item from the result.", nextEntry.get(), resultEntry);
Assert.assertFalse("hasNext() did not return false when reaching a terminal state.", r.hasNext());
resultEntry = r.next();
Assert.assertNull("next() did return null when it encountered a terminal state.", resultEntry);
}
use of io.pravega.common.util.ByteArraySegment in project pravega by pravega.
the class ContainerReadIndexTests method setupMergeRead.
/**
* Sets up a partial-merge Future Read for the two segments:
* 1. Writes some data to transactionId (both Read Index and Storage).
* 2. Calls beginMerge(parentId, transactionId)
* 3. Executes a Storage concat (transactionId -> parentId)
* 4. Clears the cache and returns a ReadResultEntry that requests data at the first offset of the merged transaction.
* NOTE: this does not call completeMerge().
*/
private ReadResultEntry setupMergeRead(long parentId, long transactionId, byte[] txnData, TestContext context) throws Exception {
int mergeOffset = 1;
UpdateableSegmentMetadata parentMetadata = context.metadata.getStreamSegmentMetadata(parentId);
UpdateableSegmentMetadata transactionMetadata = context.metadata.getStreamSegmentMetadata(transactionId);
appendSingleWrite(parentId, new ByteArraySegment(new byte[mergeOffset]), context);
context.storage.openWrite(parentMetadata.getName()).thenCompose(handle -> context.storage.write(handle, 0, new ByteArrayInputStream(new byte[mergeOffset]), mergeOffset, TIMEOUT)).join();
// Write something to the transaction, and make sure it also makes its way to Storage.
appendSingleWrite(transactionId, new ByteArraySegment(txnData), context);
val transactionWriteHandle = context.storage.openWrite(transactionMetadata.getName()).join();
context.storage.write(transactionWriteHandle, 0, new ByteArrayInputStream(txnData), txnData.length, TIMEOUT).join();
transactionMetadata.setStorageLength(transactionMetadata.getLength());
// Seal & Begin-merge the transaction (do not seal in storage).
transactionMetadata.markSealed();
parentMetadata.setLength(transactionMetadata.getLength() + mergeOffset);
context.readIndex.beginMerge(parentId, mergeOffset, transactionId);
transactionMetadata.markMerged();
// Clear the cache.
context.cacheManager.applyCachePolicy();
// Issue read from the parent and fetch the first entry (there should only be one).
ReadResult rr = context.readIndex.read(parentId, mergeOffset, txnData.length, TIMEOUT);
Assert.assertTrue("Parent Segment read indicates no data available.", rr.hasNext());
ReadResultEntry entry = rr.next();
Assert.assertEquals("Unexpected offset for read result entry.", mergeOffset, entry.getStreamSegmentOffset());
Assert.assertEquals("Served read result entry is not from storage.", ReadResultEntryType.Storage, entry.getType());
// Merge the transaction in storage. Do not complete-merge it.
transactionMetadata.markSealed();
transactionMetadata.markSealedInStorage();
transactionMetadata.markDeleted();
context.storage.seal(transactionWriteHandle, TIMEOUT).join();
val parentWriteHandle = context.storage.openWrite(parentMetadata.getName()).join();
context.storage.concat(parentWriteHandle, 1, transactionWriteHandle.getSegmentName(), TIMEOUT).join();
parentMetadata.setStorageLength(parentMetadata.getLength());
// Attempt to extract data from the read.
entry.requestContent(TIMEOUT);
Assert.assertFalse("Not expecting the read to be completed.", entry.getContent().isDone());
return entry;
}
use of io.pravega.common.util.ByteArraySegment in project pravega by pravega.
the class ContainerReadIndexTests method testStorageReadTransactionNoCache.
// region Scenario-based tests
/**
* Tests the following Scenario, where the ReadIndex would either read from a bad offset or fail with an invalid offset
* when reading in certain conditions:
* * A segment has a transaction, which has N bytes written to it.
* * The transaction is merged into its parent segment at offset M > N.
* * At least one byte of the transaction is evicted from the cache
* * A read is issued to the parent segment for that byte that was evicted
* * The ReadIndex is supposed to issue a Storage Read with an offset inside the transaction range (so translate
* from the parent's offset to the transaction's offset). However, after the read, it is supposed to look like the
* data was read from the parent segment, so it should not expose the adjusted offset at all.
* <p>
* This very specific unit test is a result of a regression found during testing.
*/
@Test
public void testStorageReadTransactionNoCache() throws Exception {
CachePolicy cachePolicy = new CachePolicy(1, Duration.ZERO, Duration.ofMillis(1));
@Cleanup TestContext context = new TestContext(DEFAULT_CONFIG, cachePolicy);
// Create parent segment and one transaction
long parentId = createSegment(0, context);
long transactionId = createTransaction(1, context);
createSegmentsInStorage(context);
ByteArrayOutputStream writtenStream = new ByteArrayOutputStream();
// Write something to the transaction, and make sure it also makes its way to Storage.
UpdateableSegmentMetadata parentMetadata = context.metadata.getStreamSegmentMetadata(parentId);
UpdateableSegmentMetadata transactionMetadata = context.metadata.getStreamSegmentMetadata(transactionId);
ByteArraySegment transactionWriteData = getAppendData(transactionMetadata.getName(), transactionId, 0, 0);
appendSingleWrite(transactionId, transactionWriteData, context);
val handle = context.storage.openWrite(transactionMetadata.getName()).join();
context.storage.write(handle, 0, transactionWriteData.getReader(), transactionWriteData.getLength(), TIMEOUT).join();
transactionMetadata.setStorageLength(transactionMetadata.getLength());
// Write some data to the parent, and make sure it is more than what we write to the transaction (hence the 10).
for (int i = 0; i < 10; i++) {
ByteArraySegment parentWriteData = getAppendData(parentMetadata.getName(), parentId, i, i);
appendSingleWrite(parentId, parentWriteData, context);
parentWriteData.copyTo(writtenStream);
}
// Seal & Begin-merge the transaction (do not seal in storage).
transactionMetadata.markSealed();
long mergeOffset = parentMetadata.getLength();
parentMetadata.setLength(mergeOffset + transactionMetadata.getLength());
context.readIndex.beginMerge(parentId, mergeOffset, transactionId);
transactionMetadata.markMerged();
transactionWriteData.copyTo(writtenStream);
// Clear the cache.
boolean evicted = context.cacheManager.applyCachePolicy();
Assert.assertTrue("Expected an eviction.", evicted);
// Issue read from the parent.
ReadResult rr = context.readIndex.read(parentId, mergeOffset, transactionWriteData.getLength(), TIMEOUT);
Assert.assertTrue("Parent Segment read indicates no data available.", rr.hasNext());
ByteArrayOutputStream readStream = new ByteArrayOutputStream();
long expectedOffset = mergeOffset;
while (rr.hasNext()) {
ReadResultEntry entry = rr.next();
Assert.assertEquals("Unexpected offset for read result entry.", expectedOffset, entry.getStreamSegmentOffset());
Assert.assertEquals("Served read result entry is not from storage.", ReadResultEntryType.Storage, entry.getType());
// Request contents and store for later use.
entry.requestContent(TIMEOUT);
BufferView contents = entry.getContent().get(TIMEOUT.toMillis(), TimeUnit.MILLISECONDS);
contents.copyTo(readStream);
expectedOffset += contents.getLength();
}
byte[] readData = readStream.toByteArray();
Assert.assertArrayEquals("Unexpected data read back.", transactionWriteData.getCopy(), readData);
}
use of io.pravega.common.util.ByteArraySegment in project pravega by pravega.
the class ContainerReadIndexTests method testCacheEviction.
/**
* Tests the ability to evict entries from the ReadIndex under various conditions:
* * If an entry is aged out
* * If an entry is pushed out because of cache space pressure.
*
* This also verifies that certain entries, such as RedirectReadIndexEntries and entries after the Storage Offset are
* not removed.
*
* The way this test goes is as follows (it's pretty subtle, because there aren't many ways to hook into the ReadIndex and see what it's doing)
* 1. It creates a bunch of segments, and populates them in storage (each) up to offset N/2-1 (this is called pre-storage)
* 2. It populates the ReadIndex for each of those segments from offset N/2 to offset N-1 (this is called post-storage)
* 3. It loads all the data from Storage into the ReadIndex, in entries of size equal to those already loaded in step #2.
* 3a. At this point, all the entries added in step #2 have Generations 0..A/4-1, and step #3 have generations A/4..A-1
* 4. Append more data at the end. This forces the generation to increase to 1.25A.
* 4a. Nothing should be evicted from the cache now, since the earliest items are all post-storage.
* 5. We 'touch' (read) the first 1/3 of pre-storage entries (offsets 0..N/4).
* 5a. At this point, those entries (offsets 0..N/6) will have the newest generations (1.25A..1.5A)
* 6. We append more data (equivalent to the data we touched)
* 6a. Nothing should be evicted, since those generations that were just eligible for removal were touched and bumped up.
* 7. We forcefully increase the current generation by 1 (without touching the ReadIndex)
* 7a. At this point, we expect all the pre-storage items, except the touched ones, to be evicted. This is generations 0.25A-0.75A.
* 8. Update the metadata and indicate that all the post-storage entries are now pre-storage and bump the generation by 0.75A.
* 8a. At this point, we expect all former post-storage items and pre-storage items to be evicted (in this order).
* <p>
* The final order of eviction (in terms of offsets, for each segment), is:
* * 0.25N-0.75N, 0.75N..N, N..1.25N, 0..0.25N, 1.25N..1.5N (remember that we added quite a bunch of items after the initial run).
*/
@Test
@SuppressWarnings("checkstyle:CyclomaticComplexity")
public void testCacheEviction() throws Exception {
// Create a CachePolicy with a set number of generations and a known max size.
// Each generation contains exactly one entry, so the number of generations is also the number of entries.
// We append one byte at each time. This allows us to test edge cases as well by having the finest precision when
// it comes to selecting which bytes we want evicted and which kept.
final int appendSize = 1;
// This also doubles as number of generations (each generation, we add one append for each segment).
final int entriesPerSegment = 100;
final int cacheMaxSize = SEGMENT_COUNT * entriesPerSegment * appendSize;
// 25% of the entries are beyond the StorageOffset
final int postStorageEntryCount = entriesPerSegment / 4;
// 75% of the entries are before the StorageOffset.
final int preStorageEntryCount = entriesPerSegment - postStorageEntryCount;
CachePolicy cachePolicy = new CachePolicy(cacheMaxSize, 1.0, 1.0, Duration.ofMillis(1000 * 2 * entriesPerSegment), Duration.ofMillis(1000));
// To properly test this, we want predictable storage reads.
ReadIndexConfig config = ReadIndexConfig.builder().with(ReadIndexConfig.STORAGE_READ_ALIGNMENT, appendSize).build();
ArrayList<Integer> removedEntries = new ArrayList<>();
@Cleanup TestContext context = new TestContext(config, cachePolicy);
// To ease our testing, we disable appends and instruct the TestCache to report the same value for UsedBytes as it
// has for StoredBytes. This shields us from having to know internal details about the layout of the cache.
context.cacheStorage.usedBytesSameAsStoredBytes = true;
context.cacheStorage.disableAppends = true;
// Record every cache removal.
context.cacheStorage.deleteCallback = removedEntries::add;
// Create the segments (metadata + storage).
ArrayList<Long> segmentIds = createSegments(context);
createSegmentsInStorage(context);
// Populate the Storage with appropriate data.
byte[] preStorageData = new byte[preStorageEntryCount * appendSize];
for (long segmentId : segmentIds) {
UpdateableSegmentMetadata sm = context.metadata.getStreamSegmentMetadata(segmentId);
val handle = context.storage.openWrite(sm.getName()).join();
context.storage.write(handle, 0, new ByteArrayInputStream(preStorageData), preStorageData.length, TIMEOUT).join();
sm.setStorageLength(preStorageData.length);
sm.setLength(preStorageData.length);
}
val cacheMappings = new HashMap<Integer, SegmentOffset>();
// Callback that appends one entry at the end of the given segment id.
Consumer<Long> appendOneEntry = segmentId -> {
UpdateableSegmentMetadata sm = context.metadata.getStreamSegmentMetadata(segmentId);
byte[] data = new byte[appendSize];
long offset = sm.getLength();
sm.setLength(offset + data.length);
try {
context.cacheStorage.insertCallback = address -> cacheMappings.put(address, new SegmentOffset(segmentId, offset));
context.readIndex.append(segmentId, offset, new ByteArraySegment(data));
} catch (StreamSegmentNotExistsException ex) {
throw new CompletionException(ex);
}
};
// Populate the ReadIndex with the Append entries (post-StorageOffset)
for (int i = 0; i < postStorageEntryCount; i++) {
segmentIds.forEach(appendOneEntry);
// Each time we make a round of appends (one per segment), we increment the generation in the CacheManager.
context.cacheManager.applyCachePolicy();
}
// Read all the data from Storage, making sure we carefully associate them with the proper generation.
for (int i = 0; i < preStorageEntryCount; i++) {
long offset = i * appendSize;
for (long segmentId : segmentIds) {
@Cleanup ReadResult result = context.readIndex.read(segmentId, offset, appendSize, TIMEOUT);
ReadResultEntry resultEntry = result.next();
Assert.assertEquals("Unexpected type of ReadResultEntry when trying to load up data into the ReadIndex Cache.", ReadResultEntryType.Storage, resultEntry.getType());
CompletableFuture<Void> insertedInCache = new CompletableFuture<>();
context.cacheStorage.insertCallback = address -> {
cacheMappings.put(address, new SegmentOffset(segmentId, offset));
insertedInCache.complete(null);
};
resultEntry.requestContent(TIMEOUT);
BufferView contents = resultEntry.getContent().get(TIMEOUT.toMillis(), TimeUnit.MILLISECONDS);
Assert.assertFalse("Not expecting more data to be available for reading.", result.hasNext());
Assert.assertEquals("Unexpected ReadResultEntry length when trying to load up data into the ReadIndex Cache.", appendSize, contents.getLength());
// Wait for the entry to be inserted into the cache before moving on.
insertedInCache.get(TIMEOUT.toMillis(), TimeUnit.MILLISECONDS);
}
context.cacheManager.applyCachePolicy();
}
Assert.assertEquals("Not expecting any removed Cache entries at this point (cache is not full).", 0, removedEntries.size());
// Append more data (equivalent to all post-storage entries), and verify that NO entries are being evicted (we cannot evict post-storage entries).
for (int i = 0; i < postStorageEntryCount; i++) {
segmentIds.forEach(appendOneEntry);
context.cacheManager.applyCachePolicy();
}
Assert.assertEquals("Not expecting any removed Cache entries at this point (only eligible entries were post-storage).", 0, removedEntries.size());
// 'Touch' the first few entries read from storage. This should move them to the back of the queue (they won't be the first ones to be evicted).
int touchCount = preStorageEntryCount / 3;
for (int i = 0; i < touchCount; i++) {
long offset = i * appendSize;
for (long segmentId : segmentIds) {
@Cleanup ReadResult result = context.readIndex.read(segmentId, offset, appendSize, TIMEOUT);
ReadResultEntry resultEntry = result.next();
Assert.assertEquals("Unexpected type of ReadResultEntry when trying to load up data into the ReadIndex Cache.", ReadResultEntryType.Cache, resultEntry.getType());
}
}
// Append more data (equivalent to the amount of data we 'touched'), and verify that the entries we just touched are not being removed..
for (int i = 0; i < touchCount; i++) {
segmentIds.forEach(appendOneEntry);
context.cacheManager.applyCachePolicy();
}
Assert.assertEquals("Not expecting any removed Cache entries at this point (we touched old entries and they now have the newest generation).", 0, removedEntries.size());
// Increment the generations so that we are caught up to just before the generation where the "touched" items now live.
context.cacheManager.applyCachePolicy();
// We expect all but the 'touchCount' pre-Storage entries to be removed.
int expectedRemovalCount = (preStorageEntryCount - touchCount) * SEGMENT_COUNT;
Assert.assertEquals("Unexpected number of removed entries after having forced out all pre-storage entries.", expectedRemovalCount, removedEntries.size());
// Now update the metadata and indicate that all the post-storage data has been moved to storage.
segmentIds.forEach(segmentId -> {
UpdateableSegmentMetadata sm = context.metadata.getStreamSegmentMetadata(segmentId);
sm.setStorageLength(sm.getLength());
});
// We add one artificial entry, which we'll be touching forever and ever; this forces the CacheManager to
// update its current generation every time. We will be ignoring this entry for our test.
SegmentMetadata readSegment = context.metadata.getStreamSegmentMetadata(segmentIds.get(0));
appendOneEntry.accept(readSegment.getId());
// Now evict everything (whether by size of by aging out).
for (int i = 0; i < cachePolicy.getMaxGenerations(); i++) {
@Cleanup ReadResult result = context.readIndex.read(readSegment.getId(), readSegment.getLength() - appendSize, appendSize, TIMEOUT);
result.next();
context.cacheManager.applyCachePolicy();
}
int expectedRemovalCountPerSegment = entriesPerSegment + touchCount + postStorageEntryCount;
int expectedTotalRemovalCount = SEGMENT_COUNT * expectedRemovalCountPerSegment;
Assert.assertEquals("Unexpected number of removed entries after having forced out all the entries.", expectedTotalRemovalCount, removedEntries.size());
// Finally, verify that the evicted items are in the correct order (for each segment). See this test's description for details.
for (long segmentId : segmentIds) {
List<SegmentOffset> segmentRemovedKeys = removedEntries.stream().map(cacheMappings::get).filter(e -> e.segmentId == segmentId).collect(Collectors.toList());
Assert.assertEquals("Unexpected number of removed entries for segment " + segmentId, expectedRemovalCountPerSegment, segmentRemovedKeys.size());
// The correct order of eviction (N=entriesPerSegment) is: 0.25N-0.75N, 0.75N..N, N..1.25N, 0..0.25N, 1.25N..1.5N.
// This is equivalent to the following tests
// 0.25N-1.25N
checkOffsets(segmentRemovedKeys, segmentId, 0, entriesPerSegment, entriesPerSegment * appendSize / 4, appendSize);
// 0..0.25N
checkOffsets(segmentRemovedKeys, segmentId, entriesPerSegment, entriesPerSegment / 4, 0, appendSize);
// 1.25N..1.5N
checkOffsets(segmentRemovedKeys, segmentId, entriesPerSegment + entriesPerSegment / 4, entriesPerSegment / 4, (int) (entriesPerSegment * appendSize * 1.25), appendSize);
}
}
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