JarCasting
buffer-slayer
buffer-slayer is tool that buffers requests and send them in batch, of which client supports batch operation. Such as Spring-JdbcTemplate(batchUpdate), Redis(pipeline).
It has a queue that allows multiple producers to send to, and limited so to keep application away from Overflowing.
Also there is a fixed sized buffer to normalize data transportation. The buffer's data will be sent when it is full or a specific timeout is reached whichever comes first.
This project is inspired by zipkin-reporter-java.
Motivation
- Consumer is always faster in batch than accepting one by one.
- When consumer is slower than producer, don't overflow application's memory.
- If a flood of requests is coming, low down the impact on the backing storage (DB, redis, etc.).
- A promise is returned for async sending. Even though messages are sent in batch, you can get a one-to-one promise from the message sent to sending result.
JdbcTemplate
bufferslayer-spring-jdbc is a buffer implementation of Spring's JdbcTemplate.
Queries are forwarded to the delegated JdbcTemplate and executed blockingly.
Updates directly goes to the reporter and returns a Promise immediately.
Quick-start
<dependency>
<groupId>io.github.tramchamploo</groupId>
<artifactId>bufferslayer-spring-jdbc</artifactId>
<version>2.0.4</version>
</dependency>
For native implementation:
<dependency>
<groupId>io.github.tramchamploo</groupId>
<artifactId>bufferslayer-boundedqueue</artifactId>
<version>2.0.4</version>
</dependency>
For rx-java implementation:
<dependency>
<groupId>io.github.tramchamploo</groupId>
<artifactId>bufferslayer-rx</artifactId>
<version>2.0.4</version>
</dependency>
AsyncReporterProperties reporterProperties = new AsyncReporterProperties()
.setFlushThreads(5)
.setSharedSenderThreads(10)
.setBufferedMaxMessages(500)
.setPendingMaxMessages(10000)
.setMetrics("inmemory")
.setMetricsExporter("http");
BatchJdbcTemplate template = new BatchJdbcTemplate(yourFormerJdbcTemplate, reporterProperties);
MessageFuture<Integer> future = template.update(...);
future.addListener(f -> {
// Your callback
});
Usage
ReporterProperties
This is where you configure all properties.
sender: Sender that messages are flushed into. Necessary but often not needed for users to configure. Implementations likeJdbcTemplatewill configure it by itself.sharedSenderThreads: Num of threads that sender execute in.timerThreads: Num of threads in scheduled executor, flushing messages at a fixed rate.flushThreads: Num of threads that flush messages to sender. They wait until a buffer is full.metrics: (inmemory, noop) metrics that records nums of sent, dropped, queued messages.metricsExporter: (http, log) exporter to let users know data of metrics.bufferedMaxMessages: Max size of buffer that sent in one batch.messageTimeoutNanos: If buffer size is not reached, flush will be invoked after this timeout.pendingMaxMessages: Max size of messages to be stashed until OverflowStrategy is triggered.pendingKeepaliveNanos: Pending queue should die if no messages queued into during in its keepalive.overflowStrategy: (DropHead, DropTail, DropBuffer, DropNew, Fail) after pendingMaxMessages is reached, the strategy will be triggered.singleKey: If this value is true, different kinds of messages will be staged in the sameSizeBoundedQueue.
Benchmark
Here is a simple jdbc benchmark result on my MacBook Pro (Retina, 13-inch, Late 2013).
Using mysql 5.7.18, keeps executing a simple INSERT INTO test.benchmark(data, time) VALUES(?, ?);
Benchmark Mode Cnt Score Error Units
AsyncBatchJdbcTemplateBenchmark.high_contention_batched thrpt 15 201510.137 ± 33755.347 ops/s
AsyncBatchJdbcTemplateBenchmark.high_contention_unbatched thrpt 15 200.427 ± 52.891 ops/s
AsyncBatchJdbcTemplateBenchmark.mild_contention_batched thrpt 15 52258.451 ± 7328.203 ops/s
AsyncBatchJdbcTemplateBenchmark.mild_contention_unbatched thrpt 15 222.447 ± 25.284 ops/s
AsyncBatchJdbcTemplateBenchmark.no_contention_batched thrpt 15 30075.936 ± 2797.128 ops/s
AsyncBatchJdbcTemplateBenchmark.no_contention_unbatched thrpt 15 145.993 ± 27.643 ops/s
Components
Reporter
It sends requests to a queue and keeps flushing them to consumer.
Sender
Sending the messages that the buffer drained in batch.
SizeBoundedQueue
A queue that bounded by a specific size. Supports multi producers in parallel. It supports overflow strategies as listed.
DropHead: drops the oldest elementDropTail: drops the youngest elementDropBuffer: drops all the buffered elementsDropNew: drops the new elementBlock: block offer thread, this can be used as a simple back-pressure strategyFail: throws an exception
Strategies above are inspired by Akka stream.
QueueManager
Manages SizeBoundedQueue's lifecycle. Be responsible for queue creation and destruction.
Buffer
A list with a fixed size that can only be drained when a timeout is reached or is full.