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RocksDB fat jar to use with Apache Flink
that contains .so files for linux32 and linux64, jnilib files for Mac OSX, and a .dll for Windows x64.
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
package org.rocksdb;
/**
* Config for rate limiter, which is used to control write rate of flush and
* compaction.
*
* @see RateLimiterConfig
*/
public class GenericRateLimiterConfig extends RateLimiterConfig {
private static final long DEFAULT_REFILL_PERIOD_MICROS = (100 * 1000);
private static final int DEFAULT_FAIRNESS = 10;
/**
* GenericRateLimiterConfig constructor
*
* @param rateBytesPerSecond this is the only parameter you want to set
* most of the time. It controls the total write rate of compaction
* and flush in bytes per second. Currently, RocksDB does not enforce
* rate limit for anything other than flush and compaction, e.g. write to WAL.
* @param refillPeriodMicros this controls how often tokens are refilled. For example,
* when rate_bytes_per_sec is set to 10MB/s and refill_period_us is set to
* 100ms, then 1MB is refilled every 100ms internally. Larger value can lead to
* burstier writes while smaller value introduces more CPU overhead.
* The default should work for most cases.
* @param fairness RateLimiter accepts high-pri requests and low-pri requests.
* A low-pri request is usually blocked in favor of hi-pri request. Currently,
* RocksDB assigns low-pri to request from compaction and high-pri to request
* from flush. Low-pri requests can get blocked if flush requests come in
* continuously. This fairness parameter grants low-pri requests permission by
* fairness chance even though high-pri requests exist to avoid starvation.
* You should be good by leaving it at default 10.
*/
public GenericRateLimiterConfig(final long rateBytesPerSecond,
final long refillPeriodMicros, final int fairness) {
rateBytesPerSecond_ = rateBytesPerSecond;
refillPeriodMicros_ = refillPeriodMicros;
fairness_ = fairness;
}
/**
* GenericRateLimiterConfig constructor
*
* @param rateBytesPerSecond this is the only parameter you want to set
* most of the time. It controls the total write rate of compaction
* and flush in bytes per second. Currently, RocksDB does not enforce
* rate limit for anything other than flush and compaction, e.g. write to WAL.
*/
public GenericRateLimiterConfig(final long rateBytesPerSecond) {
this(rateBytesPerSecond, DEFAULT_REFILL_PERIOD_MICROS, DEFAULT_FAIRNESS);
}
@Override protected long newRateLimiterHandle() {
return newRateLimiterHandle(rateBytesPerSecond_, refillPeriodMicros_,
fairness_);
}
private native long newRateLimiterHandle(long rateBytesPerSecond,
long refillPeriodMicros, int fairness);
private final long rateBytesPerSecond_;
private final long refillPeriodMicros_;
private final int fairness_;
}