private void scrubCells(
TransactionManager txManager,
Multimap<String, Cell> tableNameToCells,
long scrubTimestamp,
Transaction.TransactionType transactionType) {
for (Entry<String, Collection<Cell>> entry : tableNameToCells.asMap().entrySet()) {
String tableName = entry.getKey();
if (log.isInfoEnabled()) {
log.info(
"Attempting to immediately scrub "
+ entry.getValue().size()
+ " cells from table "
+ tableName);
}
for (List<Cell> cells : Iterables.partition(entry.getValue(), batchSizeSupplier.get())) {
Multimap<Cell, Long> timestampsToDelete =
HashMultimap.create(
keyValueService.getAllTimestamps(
tableName, ImmutableSet.copyOf(cells), scrubTimestamp));
for (Cell cell : ImmutableList.copyOf(timestampsToDelete.keySet())) {
// Don't scrub garbage collection sentinels
timestampsToDelete.remove(cell, Value.INVALID_VALUE_TIMESTAMP);
}
// If transactionType == TransactionType.AGGRESSIVE_HARD_DELETE this might
// force other transactions to abort or retry
deleteCellsAtTimestamps(txManager, tableName, timestampsToDelete, transactionType);
}
if (log.isInfoEnabled()) {
log.info(
"Immediately scrubbed " + entry.getValue().size() + " cells from table " + tableName);
}
}
}
/**
* Only instances of {@code DynamicPartitionMapImpl} are supported by this implementation.
*
* @param partitionMap Must be instance of {@code DynamicPartitionMapImpl}.
*/
@Override
public synchronized void updateMap(DynamicPartitionMap partitionMap) {
if (!(partitionMap instanceof DynamicPartitionMapImpl)) {
throw new IllegalArgumentException(
"Only instances of DynamicPartitionMapImpl are supported!");
}
DynamicPartitionMapImpl dpmi = (DynamicPartitionMapImpl) partitionMap;
storage.createTable(PARTITION_MAP_TABLE, 1234);
storage.truncateTable(PARTITION_MAP_TABLE);
storage.put(PARTITION_MAP_TABLE, dpmi.toTable(), 0L);
}
private void deleteCellsAtTimestamps(
TransactionManager txManager,
String tableName,
Multimap<Cell, Long> cellToTimestamp,
Transaction.TransactionType transactionType) {
if (!cellToTimestamp.isEmpty()) {
for (Follower follower : followers) {
follower.run(txManager, tableName, cellToTimestamp.keySet(), transactionType);
}
keyValueService.addGarbageCollectionSentinelValues(tableName, cellToTimestamp.keySet());
keyValueService.delete(tableName, cellToTimestamp);
}
}
private void sweepCells(
String tableName, Multimap<Cell, Long> cellTsPairsToSweep, Set<Cell> sentinelsToAdd) {
if (cellTsPairsToSweep.isEmpty()) {
return;
}
for (Follower follower : followers) {
follower.run(txManager, tableName, cellTsPairsToSweep.keySet(), TransactionType.HARD_DELETE);
}
if (!sentinelsToAdd.isEmpty()) {
keyValueService.addGarbageCollectionSentinelValues(tableName, sentinelsToAdd);
}
keyValueService.delete(tableName, cellTsPairsToSweep);
}
private InKvsPartitionMapService(DynamicPartitionMapImpl partitionMap, KeyValueService storage) {
this.storage = storage;
storage.createTable(PARTITION_MAP_TABLE, 1234);
if (partitionMap != null) {
updateMap(partitionMap);
}
}
private long getCommitTimestampRollBackIfNecessary(
long startTimestamp, Multimap<String, Cell> tableNameToCell) {
Long commitTimestamp = transactionService.get(startTimestamp);
if (commitTimestamp == null) {
// Roll back this transaction (note that rolling back arbitrary transactions
// can never cause correctness issues, only liveness issues)
try {
transactionService.putUnlessExists(startTimestamp, TransactionConstants.FAILED_COMMIT_TS);
} catch (KeyAlreadyExistsException e) {
String msg =
"Could not roll back transaction with start timestamp "
+ startTimestamp
+ "; either"
+ " it was already rolled back (by a different transaction), or it committed successfully"
+ " before we could roll it back.";
log.error(
"This isn't a bug but it should be very infrequent. " + msg,
new TransactionFailedRetriableException(msg, e));
}
commitTimestamp = transactionService.get(startTimestamp);
}
if (commitTimestamp == null) {
throw new RuntimeException(
"expected commit timestamp to be non-null for startTs: " + startTimestamp);
}
if (commitTimestamp == TransactionConstants.FAILED_COMMIT_TS) {
for (String table : tableNameToCell.keySet()) {
Map<Cell, Long> toDelete =
Maps2.createConstantValueMap(tableNameToCell.get(table), startTimestamp);
keyValueService.delete(table, Multimaps.forMap(toDelete));
}
}
return commitTimestamp;
}
@Override
public synchronized DynamicPartitionMapImpl getMap() {
ClosableIterator<RowResult<Value>> iterator =
storage.getRange(PARTITION_MAP_TABLE, RangeRequest.all(), 1L);
Map<Cell, byte[]> cells = Maps.newHashMap();
while (iterator.hasNext()) {
RowResult<Value> row = iterator.next();
for (Entry<Cell, Value> entry : row.getCells()) {
assert !cells.containsKey(entry.getKey());
cells.put(entry.getKey(), entry.getValue().getContents());
}
}
iterator.close();
return DynamicPartitionMapImpl.fromTable(cells);
}
@Override
public SweepResults run(String tableName, int batchSize, @Nullable byte[] startRow) {
Preconditions.checkNotNull(tableName);
Preconditions.checkState(!AtlasDbConstants.hiddenTables.contains(tableName));
if (tableName.startsWith(AtlasDbConstants.NAMESPACE_PREFIX)) {
// this happens sometimes; I think it's because some places in the code can
// start this sweeper without doing the full normally ordered KVSModule startup.
// I did check and sweep.stats did contain the FQ table name for all of the tables,
// so it is at least broken in some way that still allows namespaced tables to eventually be
// swept.
log.warn("The sweeper should not be run on tables passed through namespace mapping.");
return SweepResults.EMPTY_SWEEP;
}
// Earliest start timestamp of any currently open transaction, with two caveats:
// (1) unreadableTimestamps are calculated via wall-clock time, and so may not be correct
// under pathological clock conditions
// (2) immutableTimestamps do not account for locks have timed out after checking their locks;
// such a transaction may have a start timestamp less than the immutableTimestamp, and it
// could still get successfully committed (its commit timestamp may or may not be less than
// the immutableTimestamp
// Note that this is fine, because we'll either
// (1) force old readers to abort (if they read a garbage collection sentinel), or
// (2) force old writers to retry (note that we must roll back any uncommitted transactions that
// we encounter
SweepStrategy sweepStrategy = sweepStrategyManager.get().get(tableName);
if (sweepStrategy == null) {
sweepStrategy = SweepStrategy.CONSERVATIVE;
} else if (sweepStrategy == SweepStrategy.NOTHING) {
return SweepResults.EMPTY_SWEEP;
}
if (startRow == null) {
startRow = new byte[0];
}
RangeRequest rangeRequest =
RangeRequest.builder().startRowInclusive(startRow).batchHint(batchSize).build();
long sweepTimestamp = getSweepTimestamp(sweepStrategy);
ClosableIterator<RowResult<Value>> valueResults;
if (sweepStrategy == SweepStrategy.CONSERVATIVE) {
valueResults = ClosableIterators.wrap(ImmutableList.<RowResult<Value>>of().iterator());
} else {
valueResults = keyValueService.getRange(tableName, rangeRequest, sweepTimestamp);
}
ClosableIterator<RowResult<Set<Long>>> rowResults =
keyValueService.getRangeOfTimestamps(tableName, rangeRequest, sweepTimestamp);
try {
List<RowResult<Set<Long>>> rowResultTimestamps =
ImmutableList.copyOf(Iterators.limit(rowResults, batchSize));
PeekingIterator<RowResult<Value>> peekingValues = Iterators.peekingIterator(valueResults);
Set<Cell> sentinelsToAdd = Sets.newHashSet();
Multimap<Cell, Long> rowTimestamps =
getTimestampsFromRowResults(rowResultTimestamps, sweepStrategy);
Multimap<Cell, Long> cellTsPairsToSweep =
getCellTsPairsToSweep(
rowTimestamps, peekingValues, sweepTimestamp, sweepStrategy, sentinelsToAdd);
sweepCells(tableName, cellTsPairsToSweep, sentinelsToAdd);
byte[] nextRow =
rowResultTimestamps.size() < batchSize
? null
: RangeRequests.getNextStartRow(
false, Iterables.getLast(rowResultTimestamps).getRowName());
return new SweepResults(nextRow, rowResultTimestamps.size(), cellTsPairsToSweep.size());
} finally {
rowResults.close();
valueResults.close();
}
}