com.sleepycat.db
Class CacheStats

java.lang.Object
  com.sleepycat.db.CacheStats

public class CacheStats
extends Object

Cache statistics for a database environment.

Method Summary

long	getAlloc() Number of page allocations.
long	getAllocBuckets() Number of hash buckets checked during allocation.
long	getAllocMaxBuckets() Maximum number of hash buckets checked during an allocation.
long	getAllocMaxPages() Maximum number of pages checked during an allocation.
long	getAllocPages() Number of pages checked during allocation.
int	getBytes() Bytes of cache (total cache size is st_gbytes + st_bytes).
long	getCacheHit() Requested pages found in the cache.
long	getCacheMiss() Requested pages not found in the cache.
int	getGbytes() Gigabytes of cache (total cache size is st_gbytes + st_bytes).
int	getHashBuckets() Number of hash buckets in the buffer hash table.
long	getHashExamined() Total number of hash elements traversed during hash table lookups.
int	getHashLongest() The longest chain ever encountered in buffer hash table lookups.
long	getHashMaxNowait() The number of times a thread of control was able to obtain the hash bucket lock without waiting on the bucket which had the maximum number of times that a thread of control needed to wait.
long	getHashMaxWait() The maximum number of times any hash bucket lock was waited for by a thread of control.
int	getHashMutexes() The number of hash bucket mutexes in the buffer hash table.
long	getHashNowait() The number of times that a thread of control was able to obtain a hash bucket lock without waiting.
int	getHashSearches() Total number of buffer hash table lookups.
long	getHashWait() The number of times that a thread of control was forced to wait before obtaining a hash bucket lock.
long	getIoWait() Number of operations blocked waiting for I/O to complete.
int	getMap() Requested pages mapped into the process' address space (there is no available information about whether or not this request caused disk I/O, although examining the application page fault rate may be helpful).
int	getMaxNumCache() Maximum number of caches, as configured with EnvironmentConfig.setCacheMax(long).
int	getMaxOpenfd() Maximum number of open file descriptors.
int	getMaxWrite() The maximum number of sequential write operations scheduled by the library when flushing dirty pages from the cache.
int	getMaxWriteSleep() The number of microseconds the thread of control should pause before scheduling further write operations.
long	getMmapSize() Maximum file size for mmap.
long	getMultiversionFreed() Number of frozen buffers freed.
long	getMultiversionFrozen() Number of buffers frozen.
long	getMultiversionThawed() Number of buffers thawed.
int	getNumCache() Number of caches.
int	getPageClean() Clean pages currently in the cache.
long	getPageCreate() Pages created in the cache.
int	getPageDirty() Dirty pages currently in the cache.
long	getPageIn() Pages read into the cache.
long	getPageOut() Pages written from the cache to the backing file.
int	getPages() Pages in the cache.
int	getPageSize() Page size in bytes.
long	getPageTrickle() Dirty pages written using Environment.trickleCacheWrite.
long	getRegionNowait() The number of times that a thread of control was able to obtain a region lock without waiting.
long	getRegionWait() The number of times that a thread of control was forced to wait before obtaining a region lock.
long	getRegmax() The max size of the mutex region size.
long	getRegSize() Individual cache size.
long	getRoEvict() Clean pages forced from the cache.
long	getRwEvict() Dirty pages forced from the cache.
long	getSyncInterrupted() Number of mpool sync operations interrupted.
String	toString() For convenience, the CacheStats class has a toString method that lists all the data fields.

Methods inherited from class java.lang.Object

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

Method Detail

getGbytes

public int getGbytes()

Gigabytes of cache (total cache size is st_gbytes + st_bytes).

getBytes

public int getBytes()

Bytes of cache (total cache size is st_gbytes + st_bytes).

getNumCache

public int getNumCache()

Number of caches.

getMaxNumCache

public int getMaxNumCache()

Maximum number of caches, as configured with EnvironmentConfig.setCacheMax(long).

getMmapSize

public long getMmapSize()

Maximum file size for mmap.

getMaxOpenfd

public int getMaxOpenfd()

Maximum number of open file descriptors.

getMaxWrite

public int getMaxWrite()

The maximum number of sequential write operations scheduled by the library when flushing dirty pages from the cache.

getMaxWriteSleep

public int getMaxWriteSleep()

The number of microseconds the thread of control should pause before scheduling further write operations.

getPages

public int getPages()

Pages in the cache.

getMap

public int getMap()

Requested pages mapped into the process' address space (there is no available information about whether or not this request caused disk I/O, although examining the application page fault rate may be helpful).

getCacheHit

public long getCacheHit()

Requested pages found in the cache.

getCacheMiss

public long getCacheMiss()

Requested pages not found in the cache.

getPageCreate

public long getPageCreate()

Pages created in the cache.

getPageIn

public long getPageIn()

Pages read into the cache.

getPageOut

public long getPageOut()

Pages written from the cache to the backing file.

getRoEvict

public long getRoEvict()

Clean pages forced from the cache.

getRwEvict

public long getRwEvict()

Dirty pages forced from the cache.

getPageTrickle

public long getPageTrickle()

Dirty pages written using Environment.trickleCacheWrite.

getPageClean

public int getPageClean()

Clean pages currently in the cache.

getPageDirty

public int getPageDirty()

Dirty pages currently in the cache.

getHashBuckets

public int getHashBuckets()

Number of hash buckets in the buffer hash table.

getHashMutexes

public int getHashMutexes()

The number of hash bucket mutexes in the buffer hash table.

getPageSize

public int getPageSize()

Page size in bytes.

getHashSearches

public int getHashSearches()

Total number of buffer hash table lookups.

getHashLongest

public int getHashLongest()

The longest chain ever encountered in buffer hash table lookups.

getHashExamined

public long getHashExamined()

Total number of hash elements traversed during hash table lookups.

getHashNowait

public long getHashNowait()

The number of times that a thread of control was able to obtain a hash bucket lock without waiting.

getHashWait

public long getHashWait()

The number of times that a thread of control was forced to wait before obtaining a hash bucket lock.

getHashMaxNowait

public long getHashMaxNowait()

The number of times a thread of control was able to obtain the hash bucket lock without waiting on the bucket which had the maximum number of times that a thread of control needed to wait.

getHashMaxWait

public long getHashMaxWait()

The maximum number of times any hash bucket lock was waited for by a thread of control.

getRegionNowait

public long getRegionNowait()

The number of times that a thread of control was able to obtain a region lock without waiting.

getRegionWait

public long getRegionWait()

The number of times that a thread of control was forced to wait before obtaining a region lock.

getMultiversionFrozen

public long getMultiversionFrozen()

Number of buffers frozen.

getMultiversionThawed

public long getMultiversionThawed()

Number of buffers thawed.

getMultiversionFreed

public long getMultiversionFreed()

Number of frozen buffers freed.

getAlloc

public long getAlloc()

Number of page allocations.

getAllocBuckets

public long getAllocBuckets()

Number of hash buckets checked during allocation.

getAllocMaxBuckets

public long getAllocMaxBuckets()

Maximum number of hash buckets checked during an allocation.

getAllocPages

public long getAllocPages()

Number of pages checked during allocation.

getAllocMaxPages

public long getAllocMaxPages()

Maximum number of pages checked during an allocation.

getIoWait

public long getIoWait()

Number of operations blocked waiting for I/O to complete.

getSyncInterrupted

public long getSyncInterrupted()

Number of mpool sync operations interrupted.

getRegSize

public long getRegSize()

Individual cache size.

getRegmax

public long getRegmax()

The max size of the mutex region size.

toString

public String toString()

For convenience, the CacheStats class has a toString method that lists all the data fields.

Overrides:

toString in class Object