org.forstdb.TransactionDBOptions Maven / Gradle / Ivy
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
package org.forstdb;
public class TransactionDBOptions extends RocksObject {
public TransactionDBOptions() {
super(newTransactionDBOptions());
}
/**
* Specifies the maximum number of keys that can be locked at the same time
* per column family.
*
* If the number of locked keys is greater than {@code #getMaxNumLocks()},
* transaction writes (or GetForUpdate) will return an error.
*
* @return The maximum number of keys that can be locked
*/
public long getMaxNumLocks() {
assert(isOwningHandle());
return getMaxNumLocks(nativeHandle_);
}
/**
* Specifies the maximum number of keys that can be locked at the same time
* per column family.
*
* If the number of locked keys is greater than {@link #getMaxNumLocks()},
* transaction writes (or GetForUpdate) will return an error.
*
* @param maxNumLocks The maximum number of keys that can be locked;
* If this value is not positive, no limit will be enforced.
*
* @return this TransactionDBOptions instance
*/
public TransactionDBOptions setMaxNumLocks(final long maxNumLocks) {
assert(isOwningHandle());
setMaxNumLocks(nativeHandle_, maxNumLocks);
return this;
}
/**
* The number of sub-tables per lock table (per column family)
*
* @return The number of sub-tables
*/
public long getNumStripes() {
assert(isOwningHandle());
return getNumStripes(nativeHandle_);
}
/**
* Increasing this value will increase the concurrency by dividing the lock
* table (per column family) into more sub-tables, each with their own
* separate mutex.
*
* Default: 16
*
* @param numStripes The number of sub-tables
*
* @return this TransactionDBOptions instance
*/
public TransactionDBOptions setNumStripes(final long numStripes) {
assert(isOwningHandle());
setNumStripes(nativeHandle_, numStripes);
return this;
}
/**
* The default wait timeout in milliseconds when
* a transaction attempts to lock a key if not specified by
* {@link TransactionOptions#setLockTimeout(long)}
*
* If 0, no waiting is done if a lock cannot instantly be acquired.
* If negative, there is no timeout.
*
* @return the default wait timeout in milliseconds
*/
public long getTransactionLockTimeout() {
assert(isOwningHandle());
return getTransactionLockTimeout(nativeHandle_);
}
/**
* If positive, specifies the default wait timeout in milliseconds when
* a transaction attempts to lock a key if not specified by
* {@link TransactionOptions#setLockTimeout(long)}
*
* If 0, no waiting is done if a lock cannot instantly be acquired.
* If negative, there is no timeout. Not using a timeout is not recommended
* as it can lead to deadlocks. Currently, there is no deadlock-detection to
* recover from a deadlock.
*
* Default: 1000
*
* @param transactionLockTimeout the default wait timeout in milliseconds
*
* @return this TransactionDBOptions instance
*/
public TransactionDBOptions setTransactionLockTimeout(
final long transactionLockTimeout) {
assert(isOwningHandle());
setTransactionLockTimeout(nativeHandle_, transactionLockTimeout);
return this;
}
/**
* The wait timeout in milliseconds when writing a key
* OUTSIDE of a transaction (ie by calling {@link RocksDB#put},
* {@link RocksDB#merge}, {@link RocksDB#delete} or {@link RocksDB#write}
* directly).
*
* If 0, no waiting is done if a lock cannot instantly be acquired.
* If negative, there is no timeout and will block indefinitely when acquiring
* a lock.
*
* @return the timeout in milliseconds when writing a key OUTSIDE of a
* transaction
*/
public long getDefaultLockTimeout() {
assert(isOwningHandle());
return getDefaultLockTimeout(nativeHandle_);
}
/**
* If positive, specifies the wait timeout in milliseconds when writing a key
* OUTSIDE of a transaction (ie by calling {@link RocksDB#put},
* {@link RocksDB#merge}, {@link RocksDB#delete} or {@link RocksDB#write}
* directly).
*
* If 0, no waiting is done if a lock cannot instantly be acquired.
* If negative, there is no timeout and will block indefinitely when acquiring
* a lock.
*
* Not using a timeout can lead to deadlocks. Currently, there
* is no deadlock-detection to recover from a deadlock. While DB writes
* cannot deadlock with other DB writes, they can deadlock with a transaction.
* A negative timeout should only be used if all transactions have a small
* expiration set.
*
* Default: 1000
*
* @param defaultLockTimeout the timeout in milliseconds when writing a key
* OUTSIDE of a transaction
* @return this TransactionDBOptions instance
*/
public TransactionDBOptions setDefaultLockTimeout(final long defaultLockTimeout) {
assert (isOwningHandle());
setDefaultLockTimeout(nativeHandle_, defaultLockTimeout);
return this;
}
// /**
// * If set, the {@link TransactionDB} will use this implementation of a mutex
// * and condition variable for all transaction locking instead of the default
// * mutex/condvar implementation.
// *
// * @param transactionDbMutexFactory the mutex factory for the transactions
// *
// * @return this TransactionDBOptions instance
// */
// public TransactionDBOptions setCustomMutexFactory(
// final TransactionDBMutexFactory transactionDbMutexFactory) {
//
// }
/**
* The policy for when to write the data into the DB. The default policy is to
* write only the committed data {@link TxnDBWritePolicy#WRITE_COMMITTED}.
* The data could be written before the commit phase. The DB then needs to
* provide the mechanisms to tell apart committed from uncommitted data.
*
* @return The write policy.
*/
public TxnDBWritePolicy getWritePolicy() {
assert(isOwningHandle());
return TxnDBWritePolicy.getTxnDBWritePolicy(getWritePolicy(nativeHandle_));
}
/**
* The policy for when to write the data into the DB. The default policy is to
* write only the committed data {@link TxnDBWritePolicy#WRITE_COMMITTED}.
* The data could be written before the commit phase. The DB then needs to
* provide the mechanisms to tell apart committed from uncommitted data.
*
* @param writePolicy The write policy.
*
* @return this TransactionDBOptions instance
*/
public TransactionDBOptions setWritePolicy(
final TxnDBWritePolicy writePolicy) {
assert(isOwningHandle());
setWritePolicy(nativeHandle_, writePolicy.getValue());
return this;
}
private static native long newTransactionDBOptions();
private native long getMaxNumLocks(final long handle);
private native void setMaxNumLocks(final long handle,
final long maxNumLocks);
private native long getNumStripes(final long handle);
private native void setNumStripes(final long handle, final long numStripes);
private native long getTransactionLockTimeout(final long handle);
private native void setTransactionLockTimeout(final long handle,
final long transactionLockTimeout);
private native long getDefaultLockTimeout(final long handle);
private native void setDefaultLockTimeout(final long handle,
final long transactionLockTimeout);
private native byte getWritePolicy(final long handle);
private native void setWritePolicy(final long handle, final byte writePolicy);
@Override protected final native void disposeInternal(final long handle);
}