private int discardLast(ColumnFamily cf, int toDiscard, ColumnFamily newCf) {
boolean isReversed = isReversed();
DeletionInfo.InOrderTester tester = cf.deletionInfo().inOrderTester(isReversed);
return isReversed
? discardHead(cf, toDiscard, newCf, cf.reverseIterator(), tester)
: discardTail(cf, toDiscard, newCf, cf.iterator(), tester);
}
public Iterator<RangeTombstone> getRangeTombstoneIterator(final ColumnFamily source) {
final DeletionInfo delInfo = source.deletionInfo();
if (!delInfo.hasRanges() || slices.length == 0) return Iterators.emptyIterator();
return new AbstractIterator<RangeTombstone>() {
private int sliceIdx = 0;
private Iterator<RangeTombstone> sliceIter = currentRangeIter();
protected RangeTombstone computeNext() {
while (true) {
if (sliceIter.hasNext()) return sliceIter.next();
if (!nextSlice()) return endOfData();
sliceIter = currentRangeIter();
}
}
private Iterator<RangeTombstone> currentRangeIter() {
ColumnSlice slice = slices[reversed ? (slices.length - 1 - sliceIdx) : sliceIdx];
return reversed
? delInfo.rangeIterator(slice.finish, slice.start)
: delInfo.rangeIterator(slice.start, slice.finish);
}
private boolean nextSlice() {
return ++sliceIdx < slices.length;
}
};
}
public void trim(ColumnFamily cf, int trimTo, long now) {
// each cell can increment the count by at most one, so if we have fewer cells than trimTo, we
// can skip trimming
if (cf.getColumnCount() < trimTo) return;
ColumnCounter counter = columnCounter(cf.getComparator(), now);
Collection<Cell> cells = reversed ? cf.getReverseSortedColumns() : cf.getSortedColumns();
DeletionInfo.InOrderTester tester = cf.deletionInfo().inOrderTester(reversed);
for (Iterator<Cell> iter = cells.iterator(); iter.hasNext(); ) {
Cell cell = iter.next();
counter.count(cell, tester);
if (counter.live() > trimTo) {
iter.remove();
while (iter.hasNext()) {
iter.next();
iter.remove();
}
}
}
}
public void collectReducedColumns(
ColumnFamily container,
Iterator<Cell> reducedColumns,
DecoratedKey key,
int gcBefore,
long now) {
columnCounter = columnCounter(container.getComparator(), now);
DeletionInfo.InOrderTester tester = container.deletionInfo().inOrderTester(reversed);
while (reducedColumns.hasNext()) {
Cell cell = reducedColumns.next();
if (logger.isTraceEnabled())
logger.trace(
"collecting {} of {}: {}",
columnCounter.live(),
count,
cell.getString(container.getComparator()));
// An expired tombstone will be immediately discarded in memory, and needn't be counted.
// Neither should be any cell shadowed by a range- or a partition tombstone.
if (cell.getLocalDeletionTime() < gcBefore || !columnCounter.count(cell, tester)) continue;
if (columnCounter.live() > count) break;
if (respectTombstoneThresholds()
&& columnCounter.tombstones() > DatabaseDescriptor.getTombstoneFailureThreshold()) {
Tracing.trace(
"Scanned over {} tombstones; query aborted (see tombstone_failure_threshold); slices={}",
DatabaseDescriptor.getTombstoneFailureThreshold(),
getSlicesInfo(container));
throw new TombstoneOverwhelmingException(
columnCounter.tombstones(),
count,
container.metadata().ksName,
container.metadata().cfName,
container.getComparator().getString(cell.name()),
getSlicesInfo(container));
}
container.appendColumn(cell);
}
boolean warnTombstones =
logger.isWarnEnabled()
&& respectTombstoneThresholds()
&& columnCounter.tombstones() > DatabaseDescriptor.getTombstoneWarnThreshold();
if (warnTombstones) {
String msg =
String.format(
"Read %d live and %d tombstone cells in %s.%s for key: %1.512s (see tombstone_warn_threshold). %d columns were requested, slices=%1.512s",
columnCounter.live(),
columnCounter.tombstones(),
container.metadata().ksName,
container.metadata().cfName,
container.metadata().getKeyValidator().getString(key.getKey()),
count,
getSlicesInfo(container));
ClientWarn.warn(msg);
logger.warn(msg);
}
Tracing.trace(
"Read {} live and {} tombstone cells{}",
columnCounter.live(),
columnCounter.tombstones(),
warnTombstones ? " (see tombstone_warn_threshold)" : "");
}
private static boolean isLive(ColumnFamily cf, IColumn c) {
return c != null && !c.isMarkedForDelete() && !cf.deletionInfo().isDeleted(c);
}