@Override
public Map<String, Double> getActiveSegmentCompressionRatios() {
Map<String, Double> segmentRatios = new TreeMap<>();
for (CommitLogSegment segment : allocator.getActiveSegments())
segmentRatios.put(segment.getName(), 1.0 * segment.onDiskSize() / segment.contentSize());
return segmentRatios;
}
/**
* Modifies the per-CF dirty cursors of any commit log segments for the column family according to
* the position given. Discards any commit log segments that are no longer used.
*
* @param cfId the column family ID that was flushed
* @param context the replay position of the flush
*/
public void discardCompletedSegments(final UUID cfId, final ReplayPosition context) {
logger.trace("discard completed log segments for {}, table {}", context, cfId);
// Go thru the active segment files, which are ordered oldest to newest, marking the
// flushed CF as clean, until we reach the segment file containing the ReplayPosition passed
// in the arguments. Any segments that become unused after they are marked clean will be
// recycled or discarded.
for (Iterator<CommitLogSegment> iter = allocator.getActiveSegments().iterator();
iter.hasNext(); ) {
CommitLogSegment segment = iter.next();
segment.markClean(cfId, context);
if (segment.isUnused()) {
logger.trace("Commit log segment {} is unused", segment);
allocator.recycleSegment(segment);
} else {
logger.trace(
"Not safe to delete{} commit log segment {}; dirty is {}",
(iter.hasNext() ? "" : " active"),
segment,
segment.dirtyString());
}
// Don't mark or try to delete any newer segments once we've reached the one containing the
// position of the flush.
if (segment.contains(context)) break;
}
}
/** Forces a disk flush on the commit log files that need it. Blocking. */
public void sync(boolean syncAllSegments) {
CommitLogSegment current = allocator.allocatingFrom();
for (CommitLogSegment segment : allocator.getActiveSegments()) {
if (!syncAllSegments && segment.id > current.id) return;
segment.sync();
}
}
/**
* Delete log segments whose contents have been turned into SSTables. NOT threadsafe.
*
* <p>param @ context The commitLog context . param @ id id of the columnFamily being flushed to
* disk.
*/
private void discardCompletedSegmentsInternal(
CommitLogSegment.CommitLogContext context, Integer id) throws IOException {
if (logger.isDebugEnabled())
logger.debug("discard completed log segments for " + context + ", column family " + id + ".");
/*
* log replay assumes that we only have to look at entries past the last
* flush position, so verify that this flush happens after the last. See CASSANDRA-936
*/
assert context.position >= context.getSegment().getHeader().getPosition(id)
: "discard at "
+ context
+ " is not after last flush at "
+ context.getSegment().getHeader().getPosition(id);
/*
* Loop through all the commit log files in the history. Now process
* all files that are older than the one in the context. For each of
* these files the header needs to modified by resetting the dirty
* bit corresponding to the flushed CF.
*/
Iterator<CommitLogSegment> iter = segments.iterator();
while (iter.hasNext()) {
CommitLogSegment segment = iter.next();
CommitLogHeader header = segment.getHeader();
if (segment.equals(context.getSegment())) {
// we can't just mark the segment where the flush happened clean,
// since there may have been writes to it between when the flush
// started and when it finished. so mark the flush position as
// the replay point for this CF, instead.
if (logger.isDebugEnabled())
logger.debug("Marking replay position " + context.position + " on commit log " + segment);
header.turnOn(id, context.position);
segment.writeHeader();
break;
}
header.turnOff(id);
if (header.isSafeToDelete()) {
logger.info("Discarding obsolete commit log:" + segment);
segment.close();
DeletionService.submitDelete(segment.getHeaderPath());
DeletionService.submitDelete(segment.getPath());
// usually this will be the first (remaining) segment, but not always, if segment A contains
// writes to a CF that is unflushed but is followed by segment B whose CFs are all flushed.
iter.remove();
} else {
if (logger.isDebugEnabled())
logger.debug(
"Not safe to delete commit log " + segment + "; dirty is " + header.dirtyString());
segment.writeHeader();
}
}
}
private boolean manages(String name) {
for (CommitLogSegment segment : segments) {
if (segment.getPath().endsWith(name)) return true;
}
return false;
}
@Override
public long getActiveContentSize() {
long size = 0;
for (CommitLogSegment segment : allocator.getActiveSegments()) size += segment.contentSize();
return size;
}
public List<String> getActiveSegmentNames() {
List<String> segmentNames = new ArrayList<>();
for (CommitLogSegment segment : allocator.getActiveSegments())
segmentNames.add(segment.getName());
return segmentNames;
}