Package 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

    Modifier and Type
    Method
    Description
    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 Details

    • 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