Package io.atomix.raft.storage.log

Interface RaftLogFlusher

All Superinterfaces:

AutoCloseable, CloseableSilently

All Known Implementing Classes:

DelayedFlusher, RaftLogFlusher.DirectFlusher, RaftLogFlusher.NoopFlusher

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface RaftLogFlusher
extends CloseableSilently

Configurable flush strategy for the RaftLog. You can use its implementations to improve performance at the cost of safety.

The default strategy is RaftLogFlusher.DirectFlusher, which is the safest but slowest option.

The RaftLogFlusher.NoopFlusher is the fastest but most dangerous option, as it will defer flushing to the operating system. It's then possible to run into data corruption or data loss issues. Please refer to the documentation regarding this.

DelayedFlusher can be configured to provide a trade-off between performance and safety. This will cause flushes to be performed in a delayed fashion. See its documentation for more. You should pick this if RaftLogFlusher.DirectFlusher does not provide the desired performance, but you still wish a lower likelihood of corruption issues than with RaftLogFlusher.NoopFlusher. The recommended configuration would be to find the smallest possible delay with which you achieve your performance goals.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static final class	RaftLogFlusher.DirectFlusher	An implementation of RaftLogFlusher which flushes immediately in a blocking fashion.
static interface	RaftLogFlusher.Factory	Factory methods to create a new RaftLogFlusher.
static final class	RaftLogFlusher.NoopFlusher	An implementation of RaftLogFlusher which does nothing.

Method Summary

Modifier and Type	Method	Description
default void	close()
void	flush(Journal journal)	Signals that there is data to be flushed in the journal.
default boolean	isDirect()	If this returns true, then any calls to flush(Journal) are synchronous and immediate, and any guarantees offered by the implementation will hold after a call to flush(Journal).

Method Details

flush

void flush(Journal journal)

Signals that there is data to be flushed in the journal. The implementation may or may not immediately flush this.

Parameters:

journal - the journal to flush

isDirect

default boolean isDirect()

If this returns true, then any calls to flush(Journal) are synchronous and immediate, and any guarantees offered by the implementation will hold after a call to flush(Journal).

close

default void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface CloseableSilently