Berkeley DB
version 4.5.20

com.sleepycat.db
Class CacheStats

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

public class CacheStats
extends Object

Cache statistics for a database environment.


Method Summary
 int getAlloc()
          Number of page allocations.
 int getAllocBuckets()
          Number of hash buckets checked during allocation.
 int getAllocMaxBuckets()
          Maximum number of hash buckets checked during an allocation.
 int getAllocMaxPages()
          Maximum number of pages checked during an allocation.
 int getAllocPages()
          Number of pages checked during allocation.
 int getBytes()
          Bytes of cache (total cache size is st_gbytes + st_bytes).
 int getCacheHit()
          Requested pages found in the cache.
 int 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 buffer hash table.
 int getHashExamined()
          Total number of hash elements traversed during hash table lookups.
 int getHashLongest()
          The longest chain ever encountered in buffer hash table lookups.
 int getHashMaxWait()
          The maximum number of times any hash bucket lock was waited for by a thread of control.
 int 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.
 int getHashWait()
          The number of times that a thread of control was forced to wait before obtaining a hash bucket lock.
 int 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 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.
 int getMmapSize()
          Maximum file size for mmap.
 int getMultiversionFreed()
          Number of frozen buffers freed.
 int getMultiversionFrozen()
          Number of buffers frozen.
 int getMultiversionThawed()
          Number of buffers thawed.
 int getNumCache()
          Number of caches.
 int getPageClean()
          Clean pages currently in the cache.
 int getPageCreate()
          Pages created in the cache.
 int getPageDirty()
          Dirty pages currently in the cache.
 int getPageIn()
          Pages read into the cache.
 int getPageOut()
          Pages written from the cache to the backing file.
 int getPages()
          Pages in the cache.
 int getPageTrickle()
          Dirty pages written using Environment.trickleCacheWrite.
 int getRegionNowait()
          The number of times that a thread of control was able to obtain a region lock without waiting.
 int getRegionWait()
          The number of times that a thread of control was forced to wait before obtaining a region lock.
 int getRegSize()
          Individual cache size.
 int getRoEvict()
          Clean pages forced from the cache.
 int getRwEvict()
          Dirty pages forced from the cache.
 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.


getRegSize

public int getRegSize()
Individual cache size.


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).


getMmapSize

public int 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.


getCacheHit

public int getCacheHit()
Requested pages found in the cache.


getCacheMiss

public int getCacheMiss()
Requested pages not found in the cache.


getPageCreate

public int getPageCreate()
Pages created in the cache.


getPageIn

public int getPageIn()
Pages read into the cache.


getPageOut

public int getPageOut()
Pages written from the cache to the backing file.


getRoEvict

public int getRoEvict()
Clean pages forced from the cache.


getRwEvict

public int getRwEvict()
Dirty pages forced from the cache.


getPageTrickle

public int getPageTrickle()
Dirty pages written using Environment.trickleCacheWrite.


getPages

public int getPages()
Pages in the cache.


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 buffer hash table.


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 int getHashExamined()
Total number of hash elements traversed during hash table lookups.


getHashNowait

public int getHashNowait()
The number of times that a thread of control was able to obtain a hash bucket lock without waiting.


getHashWait

public int getHashWait()
The number of times that a thread of control was forced to wait before obtaining a hash bucket lock.


getHashMaxWait

public int getHashMaxWait()
The maximum number of times any hash bucket lock was waited for by a thread of control.


getRegionNowait

public int getRegionNowait()
The number of times that a thread of control was able to obtain a region lock without waiting.


getRegionWait

public int getRegionWait()
The number of times that a thread of control was forced to wait before obtaining a region lock.


getMultiversionFrozen

public int getMultiversionFrozen()
Number of buffers frozen.


getMultiversionThawed

public int getMultiversionThawed()
Number of buffers thawed.


getMultiversionFreed

public int getMultiversionFreed()
Number of frozen buffers freed.


getAlloc

public int getAlloc()
Number of page allocations.


getAllocBuckets

public int getAllocBuckets()
Number of hash buckets checked during allocation.


getAllocMaxBuckets

public int getAllocMaxBuckets()
Maximum number of hash buckets checked during an allocation.


getAllocPages

public int getAllocPages()
Number of pages checked during allocation.


getAllocMaxPages

public int getAllocMaxPages()
Maximum number of pages checked during an allocation.


getIoWait

public int getIoWait()
Number of operations blocked waiting for I/O to complete.


toString

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

Overrides:
toString in class Object

Berkeley DB
version 4.5.20

Copyright(c) 1996-2006 Oracle Corporation - All rights reserved.