org.apache.cassandra.config

Class DatabaseDescriptor

java.lang.Object

org.apache.cassandra.config.DatabaseDescriptor

public class DatabaseDescriptor
extends java.lang.Object

Constructor Summary

Constructors

Constructor and Description
DatabaseDescriptor()

Method Summary

Modifier and Type	Method and Description
static void	createAllDirectories() Creates all storage-related directories.
static java.lang.String[]	getAllDataFileLocations()
static IAuthenticator	getAuthenticator()
static IAuthorizer	getAuthorizer()
static int	getBatchlogReplayThrottleInKB()
static int	getBatchSizeWarnThreshold()
static java.net.InetAddress	getBroadcastAddress()
static java.net.InetAddress	getBroadcastRpcAddress()
static long	getCasContentionTimeout()
static EncryptionOptions.ClientEncryptionOptions	getClientEncryptionOptions()
static java.lang.String	getClusterName()
static int	getColumnIndexSize()
static Config.CommitFailurePolicy	getCommitFailurePolicy()
static java.lang.String	getCommitLogLocation()
static int	getCommitLogPeriodicQueueSize()
static boolean	getCommitLogSegmentRecyclingEnabled()
static int	getCommitLogSegmentSize() size of commitlog segments to allocate
static Config.CommitLogSync	getCommitLogSync()
static double	getCommitLogSyncBatchWindow()
static int	getCommitLogSyncPeriod()
static int	getCompactionLargePartitionWarningThreshold()
static int	getCompactionThroughputMbPerSec()
static int	getConcurrentCompactors()
static int	getConcurrentCounterWriters()
static int	getConcurrentReaders()
static int	getConcurrentWriters()
static int	getCounterCacheKeysToSave()
static int	getCounterCacheSavePeriod()
static long	getCounterCacheSizeInMB()
static long	getCounterWriteRpcTimeout()
static boolean	getDisableSTCSInL0()
static Config.DiskAccessMode	getDiskAccessMode()
static Config.DiskFailurePolicy	getDiskFailurePolicy()
static double	getDynamicBadnessThreshold()
static int	getDynamicResetInterval()
static int	getDynamicUpdateInterval()
static IEndpointSnitch	getEndpointSnitch()
static int	getFileCacheSizeInMB()
static int	getFlushWriters()
static long	getGCWarnThreshold()
static int	getHintedHandoffThrottleInKB()
static Config.DiskAccessMode	getIndexAccessMode()
static java.lang.Integer	getIndexInterval() Deprecated.
static long	getIndexSummaryCapacityInMB()
static int	getIndexSummaryResizeIntervalInMinutes()
static java.util.Collection<java.lang.String>	getInitialTokens()
static int	getInterDCStreamThroughputOutboundMegabitsPerSec()
static boolean	getInterDCTcpNoDelay()
static IInternodeAuthenticator	getInternodeAuthenticator()
static java.lang.Integer	getInternodeRecvBufferSize()
static java.lang.Integer	getInternodeSendBufferSize()
static int	getKeyCacheKeysToSave()
static int	getKeyCacheSavePeriod()
static long	getKeyCacheSizeInMB()
static java.net.InetAddress	getListenAddress()
static java.util.Comparator<java.net.InetAddress>	getLocalComparator()
static java.lang.String	getLocalDataCenter()
static int	getMaxHintsThread()
static int	getMaxHintWindow()
static int	getMaxStreamingRetries()
static MemtablePool	getMemtableAllocatorPool()
static long	getMinRpcTimeout()
static java.lang.Long	getNativeTransportMaxConcurrentConnections()
static java.lang.Long	getNativeTransportMaxConcurrentConnectionsPerIp()
static int	getNativeTransportMaxFrameSize()
static java.lang.Integer	getNativeTransportMaxThreads()
static int	getNativeTransportPort()
static java.lang.Integer	getNumTokens()
static IAllocator	getoffHeapMemoryAllocator()
static java.lang.String	getOtcCoalescingStrategy()
static int	getOtcCoalescingWindow()
static IPartitioner	getPartitioner()
static java.lang.String	getPartitionerName()
static int	getPermissionsCacheMaxEntries()
static int	getPermissionsUpdateInterval()
static int	getPermissionsValidity()
static double	getPhiConvictThreshold()
static long	getRangeRpcTimeout()
static long	getReadRpcTimeout()
static java.net.InetAddress	getReplaceAddress()
static java.util.UUID	getReplaceNode()
static java.util.Collection<java.lang.String>	getReplaceTokens()
static IRequestScheduler	getRequestScheduler()
static Config.RequestSchedulerId	getRequestSchedulerId()
static RequestSchedulerOptions	getRequestSchedulerOptions()
static int	getRowCacheKeysToSave()
static int	getRowCacheSavePeriod()
static long	getRowCacheSizeInMB()
static java.net.InetAddress	getRpcAddress()
static boolean	getRpcKeepAlive()
static int	getRpcListenBacklog()
static java.lang.Integer	getRpcMaxThreads()
static java.lang.Integer	getRpcMinThreads()
static int	getRpcPort()
static java.lang.Integer	getRpcRecvBufferSize()
static java.lang.Integer	getRpcSendBufferSize()
static java.lang.String	getRpcServerType()
static long	getRpcTimeout()
static java.lang.String	getSavedCachesLocation()
static java.util.Set<java.net.InetAddress>	getSeeds()
static java.io.File	getSerializedCachePath(CacheService.CacheType cacheType, java.lang.String version)
static EncryptionOptions.ServerEncryptionOptions	getServerEncryptionOptions()
static int	getSSLStoragePort()
static int	getSSTablePreempiveOpenIntervalInMB()
static int	getStoragePort()
static int	getStreamingSocketTimeout()
static int	getStreamThroughputOutboundMegabitsPerSec()
static int	getThriftFramedTransportSize()
static long	getTimeout(MessagingService.Verb verb)
static int	getTombstoneFailureThreshold()
static int	getTombstoneWarnThreshold()
static long	getTotalCommitlogSpaceInMB()
static boolean	getTrickleFsync()
static int	getTrickleFsyncIntervalInKb()
static long	getTruncateRpcTimeout()
static long	getWriteRpcTimeout()
static boolean	hasCrossNodeTimeout()
static boolean	hasLargeAddressSpace()
static boolean	hintedHandoffEnabled()
static boolean	hintedHandoffEnabled(java.lang.String dcName)
static java.util.Set<java.lang.String>	hintedHandoffEnabledByDC()
static Config.InternodeCompression	internodeCompression()
static boolean	isAutoBootstrap()
static boolean	isAutoSnapshot()
static boolean	isIncrementalBackupsEnabled()
static boolean	isReplacing()
static boolean	isSnapshotBeforeCompaction()
static Config	loadConfig()
static void	loadSchemas() load keyspace (keyspace) definitions, but do not initialize the keyspace instances.
static void	loadSchemas(boolean updateVersion) Load schema definitions.
static void	setAutoSnapshot(boolean autoSnapshot)
static void	setBroadcastAddress(java.net.InetAddress broadcastAdd)
static void	setBroadcastRpcAddress(java.net.InetAddress broadcastRPCAddr)
static void	setCasContentionTimeout(java.lang.Long timeOutInMillis)
static void	setCommitFailurePolicy(Config.CommitFailurePolicy policy)
static void	setCompactionThroughputMbPerSec(int value)
static void	setCounterCacheKeysToSave(int counterCacheKeysToSave)
static void	setCounterCacheSavePeriod(int counterCacheSavePeriod)
static void	setCounterWriteRpcTimeout(java.lang.Long timeOutInMillis)
static void	setDiskFailurePolicy(Config.DiskFailurePolicy policy)
static void	setDynamicBadnessThreshold(java.lang.Double dynamicBadnessThreshold)
static void	setDynamicResetInterval(java.lang.Integer dynamicResetInterval)
static void	setDynamicUpdateInterval(java.lang.Integer dynamicUpdateInterval)
static void	setEndpointSnitch(IEndpointSnitch eps)
static void	setHintedHandoffEnabled(boolean hintedHandoffEnabled)
static void	setHintedHandoffEnabled(java.lang.String dcNames)
static void	setHintedHandoffThrottleInKB(java.lang.Integer throttleInKB)
static void	setIncrementalBackupsEnabled(boolean value)
static void	setInterDCStreamThroughputOutboundMegabitsPerSec(int value)
static void	setKeyCacheKeysToSave(int keyCacheKeysToSave)
static void	setKeyCacheSavePeriod(int keyCacheSavePeriod)
static void	setMaxHintWindow(int ms)
static void	setNativeTransportMaxConcurrentConnections(long nativeTransportMaxConcurrentConnections)
static void	setNativeTransportMaxConcurrentConnectionsPerIp(long native_transport_max_concurrent_connections_per_ip)
static void	setPartitioner(IPartitioner newPartitioner)
static void	setPermissionsUpdateInterval(int updateInterval)
static void	setPermissionsValidity(int timeout)
static void	setPhiConvictThreshold(double phiConvictThreshold)
static void	setRangeRpcTimeout(java.lang.Long timeOutInMillis)
static void	setReadRpcTimeout(java.lang.Long timeOutInMillis)
static void	setRowCacheKeysToSave(int rowCacheKeysToSave)
static void	setRowCacheSavePeriod(int rowCacheSavePeriod)
static void	setRowCacheSizeInMB(long val)
static void	setRpcTimeout(java.lang.Long timeOutInMillis)
static void	setStreamThroughputOutboundMegabitsPerSec(int value)
static void	setTombstoneFailureThreshold(int threshold)
static void	setTombstoneWarnThreshold(int threshold)
static void	setTruncateRpcTimeout(java.lang.Long timeOutInMillis)
static void	setWriteRpcTimeout(java.lang.Long timeOutInMillis)
static boolean	shouldHintByDC()
static boolean	startNativeTransport()
static boolean	startRpc()
static java.util.Collection<java.lang.String>	tokensFromString(java.lang.String tokenString)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DatabaseDescriptor

public DatabaseDescriptor()

Method Detail

loadConfig

public static Config loadConfig()
                         throws ConfigurationException

Throws:

ConfigurationException

loadSchemas

public static void loadSchemas()

load keyspace (keyspace) definitions, but do not initialize the keyspace instances. Schema version may be updated as the result.

loadSchemas

public static void loadSchemas(boolean updateVersion)

Load schema definitions.

Parameters:

updateVersion - true if schema version needs to be updated

getAuthenticator

public static IAuthenticator getAuthenticator()

getAuthorizer

public static IAuthorizer getAuthorizer()

getPermissionsValidity

public static int getPermissionsValidity()

setPermissionsValidity

public static void setPermissionsValidity(int timeout)

getPermissionsCacheMaxEntries

public static int getPermissionsCacheMaxEntries()

getPermissionsUpdateInterval

public static int getPermissionsUpdateInterval()

setPermissionsUpdateInterval

public static void setPermissionsUpdateInterval(int updateInterval)

getThriftFramedTransportSize

public static int getThriftFramedTransportSize()

createAllDirectories

public static void createAllDirectories()

Creates all storage-related directories.

getPartitioner

public static IPartitioner getPartitioner()

getPartitionerName

public static java.lang.String getPartitionerName()

setPartitioner

public static void setPartitioner(IPartitioner newPartitioner)

getEndpointSnitch

public static IEndpointSnitch getEndpointSnitch()

setEndpointSnitch

public static void setEndpointSnitch(IEndpointSnitch eps)

getRequestScheduler

public static IRequestScheduler getRequestScheduler()

getRequestSchedulerOptions

public static RequestSchedulerOptions getRequestSchedulerOptions()

getRequestSchedulerId

public static Config.RequestSchedulerId getRequestSchedulerId()

getColumnIndexSize

public static int getColumnIndexSize()

getBatchSizeWarnThreshold

public static int getBatchSizeWarnThreshold()

getInitialTokens

public static java.util.Collection<java.lang.String> getInitialTokens()

tokensFromString

public static java.util.Collection<java.lang.String> tokensFromString(java.lang.String tokenString)

getNumTokens

public static java.lang.Integer getNumTokens()

getReplaceAddress

public static java.net.InetAddress getReplaceAddress()

getReplaceTokens

public static java.util.Collection<java.lang.String> getReplaceTokens()

getReplaceNode

public static java.util.UUID getReplaceNode()

isReplacing

public static boolean isReplacing()

getClusterName

public static java.lang.String getClusterName()

getMaxStreamingRetries

public static int getMaxStreamingRetries()

getStoragePort

public static int getStoragePort()

getSSLStoragePort

public static int getSSLStoragePort()

getRpcPort

public static int getRpcPort()

getRpcListenBacklog

public static int getRpcListenBacklog()

getRpcTimeout

public static long getRpcTimeout()

setRpcTimeout

public static void setRpcTimeout(java.lang.Long timeOutInMillis)

getReadRpcTimeout

public static long getReadRpcTimeout()

setReadRpcTimeout

public static void setReadRpcTimeout(java.lang.Long timeOutInMillis)

getRangeRpcTimeout

public static long getRangeRpcTimeout()

setRangeRpcTimeout

public static void setRangeRpcTimeout(java.lang.Long timeOutInMillis)

getWriteRpcTimeout

public static long getWriteRpcTimeout()

setWriteRpcTimeout

public static void setWriteRpcTimeout(java.lang.Long timeOutInMillis)

getCounterWriteRpcTimeout

public static long getCounterWriteRpcTimeout()

setCounterWriteRpcTimeout

public static void setCounterWriteRpcTimeout(java.lang.Long timeOutInMillis)

getCasContentionTimeout

public static long getCasContentionTimeout()

setCasContentionTimeout

public static void setCasContentionTimeout(java.lang.Long timeOutInMillis)

getTruncateRpcTimeout

public static long getTruncateRpcTimeout()

setTruncateRpcTimeout

public static void setTruncateRpcTimeout(java.lang.Long timeOutInMillis)

hasCrossNodeTimeout

public static boolean hasCrossNodeTimeout()

getTimeout

public static long getTimeout(MessagingService.Verb verb)

getMinRpcTimeout

public static long getMinRpcTimeout()

Returns:

the minimum configured {read, write, range, truncate, misc} timeout

getPhiConvictThreshold

public static double getPhiConvictThreshold()

setPhiConvictThreshold

public static void setPhiConvictThreshold(double phiConvictThreshold)

getConcurrentReaders

public static int getConcurrentReaders()

getConcurrentWriters

public static int getConcurrentWriters()

getConcurrentCounterWriters

public static int getConcurrentCounterWriters()

getFlushWriters

public static int getFlushWriters()

getConcurrentCompactors

public static int getConcurrentCompactors()

getCompactionThroughputMbPerSec

public static int getCompactionThroughputMbPerSec()

setCompactionThroughputMbPerSec

public static void setCompactionThroughputMbPerSec(int value)

getCompactionLargePartitionWarningThreshold

public static int getCompactionLargePartitionWarningThreshold()

getDisableSTCSInL0

public static boolean getDisableSTCSInL0()

getStreamThroughputOutboundMegabitsPerSec

public static int getStreamThroughputOutboundMegabitsPerSec()

setStreamThroughputOutboundMegabitsPerSec

public static void setStreamThroughputOutboundMegabitsPerSec(int value)

getInterDCStreamThroughputOutboundMegabitsPerSec

public static int getInterDCStreamThroughputOutboundMegabitsPerSec()

setInterDCStreamThroughputOutboundMegabitsPerSec

public static void setInterDCStreamThroughputOutboundMegabitsPerSec(int value)

getAllDataFileLocations

public static java.lang.String[] getAllDataFileLocations()

getCommitLogLocation

public static java.lang.String getCommitLogLocation()

getTombstoneWarnThreshold

public static int getTombstoneWarnThreshold()

setTombstoneWarnThreshold

public static void setTombstoneWarnThreshold(int threshold)

getTombstoneFailureThreshold

public static int getTombstoneFailureThreshold()

setTombstoneFailureThreshold

public static void setTombstoneFailureThreshold(int threshold)

getCommitLogSegmentRecyclingEnabled

public static boolean getCommitLogSegmentRecyclingEnabled()

getCommitLogSegmentSize

public static int getCommitLogSegmentSize()

size of commitlog segments to allocate

getSavedCachesLocation

public static java.lang.String getSavedCachesLocation()

getSeeds

public static java.util.Set<java.net.InetAddress> getSeeds()

getListenAddress

public static java.net.InetAddress getListenAddress()

getBroadcastAddress

public static java.net.InetAddress getBroadcastAddress()

getInternodeAuthenticator

public static IInternodeAuthenticator getInternodeAuthenticator()

setBroadcastAddress

public static void setBroadcastAddress(java.net.InetAddress broadcastAdd)

startRpc

public static boolean startRpc()

getRpcAddress

public static java.net.InetAddress getRpcAddress()

setBroadcastRpcAddress

public static void setBroadcastRpcAddress(java.net.InetAddress broadcastRPCAddr)

getBroadcastRpcAddress

public static java.net.InetAddress getBroadcastRpcAddress()

getRpcServerType

public static java.lang.String getRpcServerType()

getRpcKeepAlive

public static boolean getRpcKeepAlive()

getRpcMinThreads

public static java.lang.Integer getRpcMinThreads()

getRpcMaxThreads

public static java.lang.Integer getRpcMaxThreads()

getRpcSendBufferSize

public static java.lang.Integer getRpcSendBufferSize()

getRpcRecvBufferSize

public static java.lang.Integer getRpcRecvBufferSize()

getInternodeSendBufferSize

public static java.lang.Integer getInternodeSendBufferSize()

getInternodeRecvBufferSize

public static java.lang.Integer getInternodeRecvBufferSize()

startNativeTransport

public static boolean startNativeTransport()

getNativeTransportPort

public static int getNativeTransportPort()

getNativeTransportMaxThreads

public static java.lang.Integer getNativeTransportMaxThreads()

getNativeTransportMaxFrameSize

public static int getNativeTransportMaxFrameSize()

getNativeTransportMaxConcurrentConnections

public static java.lang.Long getNativeTransportMaxConcurrentConnections()

setNativeTransportMaxConcurrentConnections

public static void setNativeTransportMaxConcurrentConnections(long nativeTransportMaxConcurrentConnections)

getNativeTransportMaxConcurrentConnectionsPerIp

public static java.lang.Long getNativeTransportMaxConcurrentConnectionsPerIp()

setNativeTransportMaxConcurrentConnectionsPerIp

public static void setNativeTransportMaxConcurrentConnectionsPerIp(long native_transport_max_concurrent_connections_per_ip)

getCommitLogSyncBatchWindow

public static double getCommitLogSyncBatchWindow()

getCommitLogSyncPeriod

public static int getCommitLogSyncPeriod()

getCommitLogPeriodicQueueSize

public static int getCommitLogPeriodicQueueSize()

getCommitLogSync

public static Config.CommitLogSync getCommitLogSync()

getDiskAccessMode

public static Config.DiskAccessMode getDiskAccessMode()

getIndexAccessMode

public static Config.DiskAccessMode getIndexAccessMode()

setDiskFailurePolicy

public static void setDiskFailurePolicy(Config.DiskFailurePolicy policy)

getDiskFailurePolicy

public static Config.DiskFailurePolicy getDiskFailurePolicy()

setCommitFailurePolicy

public static void setCommitFailurePolicy(Config.CommitFailurePolicy policy)

getCommitFailurePolicy

public static Config.CommitFailurePolicy getCommitFailurePolicy()

isSnapshotBeforeCompaction

public static boolean isSnapshotBeforeCompaction()

isAutoSnapshot

public static boolean isAutoSnapshot()

setAutoSnapshot

public static void setAutoSnapshot(boolean autoSnapshot)

isAutoBootstrap

public static boolean isAutoBootstrap()

setHintedHandoffEnabled

public static void setHintedHandoffEnabled(boolean hintedHandoffEnabled)

setHintedHandoffEnabled

public static void setHintedHandoffEnabled(java.lang.String dcNames)

hintedHandoffEnabled

public static boolean hintedHandoffEnabled()

hintedHandoffEnabledByDC

public static java.util.Set<java.lang.String> hintedHandoffEnabledByDC()

shouldHintByDC

public static boolean shouldHintByDC()

hintedHandoffEnabled

public static boolean hintedHandoffEnabled(java.lang.String dcName)

setMaxHintWindow

public static void setMaxHintWindow(int ms)

getMaxHintWindow

public static int getMaxHintWindow()

getIndexInterval

@Deprecated
public static java.lang.Integer getIndexInterval()

Deprecated.

getSerializedCachePath

public static java.io.File getSerializedCachePath(CacheService.CacheType cacheType,
                                                  java.lang.String version)

getDynamicUpdateInterval

public static int getDynamicUpdateInterval()

setDynamicUpdateInterval

public static void setDynamicUpdateInterval(java.lang.Integer dynamicUpdateInterval)

getDynamicResetInterval

public static int getDynamicResetInterval()

setDynamicResetInterval

public static void setDynamicResetInterval(java.lang.Integer dynamicResetInterval)

getDynamicBadnessThreshold

public static double getDynamicBadnessThreshold()

setDynamicBadnessThreshold

public static void setDynamicBadnessThreshold(java.lang.Double dynamicBadnessThreshold)

getServerEncryptionOptions

public static EncryptionOptions.ServerEncryptionOptions getServerEncryptionOptions()

getClientEncryptionOptions

public static EncryptionOptions.ClientEncryptionOptions getClientEncryptionOptions()

getHintedHandoffThrottleInKB

public static int getHintedHandoffThrottleInKB()

getBatchlogReplayThrottleInKB

public static int getBatchlogReplayThrottleInKB()

setHintedHandoffThrottleInKB

public static void setHintedHandoffThrottleInKB(java.lang.Integer throttleInKB)

getMaxHintsThread

public static int getMaxHintsThread()

isIncrementalBackupsEnabled

public static boolean isIncrementalBackupsEnabled()

setIncrementalBackupsEnabled

public static void setIncrementalBackupsEnabled(boolean value)

getFileCacheSizeInMB

public static int getFileCacheSizeInMB()

getTotalCommitlogSpaceInMB

public static long getTotalCommitlogSpaceInMB()

getSSTablePreempiveOpenIntervalInMB

public static int getSSTablePreempiveOpenIntervalInMB()

getTrickleFsync

public static boolean getTrickleFsync()

getTrickleFsyncIntervalInKb

public static int getTrickleFsyncIntervalInKb()

getKeyCacheSizeInMB

public static long getKeyCacheSizeInMB()

getIndexSummaryCapacityInMB

public static long getIndexSummaryCapacityInMB()

getKeyCacheSavePeriod

public static int getKeyCacheSavePeriod()

setKeyCacheSavePeriod

public static void setKeyCacheSavePeriod(int keyCacheSavePeriod)

getKeyCacheKeysToSave

public static int getKeyCacheKeysToSave()

setKeyCacheKeysToSave

public static void setKeyCacheKeysToSave(int keyCacheKeysToSave)

getRowCacheSizeInMB

public static long getRowCacheSizeInMB()

setRowCacheSizeInMB

public static void setRowCacheSizeInMB(long val)

getRowCacheSavePeriod

public static int getRowCacheSavePeriod()

setRowCacheSavePeriod

public static void setRowCacheSavePeriod(int rowCacheSavePeriod)

getRowCacheKeysToSave

public static int getRowCacheKeysToSave()

getCounterCacheSizeInMB

public static long getCounterCacheSizeInMB()

getCounterCacheSavePeriod

public static int getCounterCacheSavePeriod()

setCounterCacheSavePeriod

public static void setCounterCacheSavePeriod(int counterCacheSavePeriod)

getCounterCacheKeysToSave

public static int getCounterCacheKeysToSave()

setCounterCacheKeysToSave

public static void setCounterCacheKeysToSave(int counterCacheKeysToSave)

getoffHeapMemoryAllocator

public static IAllocator getoffHeapMemoryAllocator()

setRowCacheKeysToSave

public static void setRowCacheKeysToSave(int rowCacheKeysToSave)

getStreamingSocketTimeout

public static int getStreamingSocketTimeout()

getLocalDataCenter

public static java.lang.String getLocalDataCenter()

getLocalComparator

public static java.util.Comparator<java.net.InetAddress> getLocalComparator()

internodeCompression

public static Config.InternodeCompression internodeCompression()

getInterDCTcpNoDelay

public static boolean getInterDCTcpNoDelay()

getMemtableAllocatorPool

public static MemtablePool getMemtableAllocatorPool()

getIndexSummaryResizeIntervalInMinutes

public static int getIndexSummaryResizeIntervalInMinutes()

hasLargeAddressSpace

public static boolean hasLargeAddressSpace()

getOtcCoalescingStrategy

public static java.lang.String getOtcCoalescingStrategy()

getOtcCoalescingWindow

public static int getOtcCoalescingWindow()

getGCWarnThreshold

public static long getGCWarnThreshold()