-CacheStats (Oracle - Berkeley DB Java API) -

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

+
+

public class CacheStats
+extends java.lang.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 +

+ + +

Method Summary

+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + + + + + + + + + + + + + + + + + + + + + + + + + + + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Methods
Modifier and Type	Method and 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 + 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`

- -

- + 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

getMultiversionReused() +

Number of outdated intermediate versions reused.

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 + cache region mutex without waiting.

long

getRegionWait() +

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

long

getRegmax() +

The maximum size, in bytes, of the mutex region.

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.

java.lang.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 +
- + + +
  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 + 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
-
-
-
-
-
+ 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 + cache region mutex without waiting.
+

+ + + +

+
getRegionWait
+
```
public long getRegionWait()
```
+
The number of times that a thread of control was forced to wait + before obtaining a cache region mutex.
+

+ + + +

+
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.
+

+ + + +

+
getMultiversionReused
+
```
public long getMultiversionReused()
```
+
Number of outdated intermediate versions reused.
+

+ + + +

+
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 maximum size, in bytes, of the mutex region.
+

+ + + +

+
toString
+
```
public java.lang.String toString()
```
+
For convenience, the CacheStats class has a toString method that + lists all the data fields.
+
+
Overrides:
+
toString in class java.lang.Object
+
+

+ + + + +

- -com.sleepycat.db - -Class CacheStats

Class CacheStats

Method Summary

Methods inherited from class java.lang.Object

-getGbytes

-getBytes

-getNumCache

-getMaxNumCache

-getMmapSize

-getMaxOpenfd

-getMaxWrite

-getMaxWriteSleep

-getPages

-getMap

Method Detail

getGbytes

getBytes

getNumCache

getMaxNumCache

getMmapSize

getMaxOpenfd

getMaxWrite

getMaxWriteSleep

getPages

getMap

-getCacheHit

-getCacheMiss

-getPageCreate

-getPageIn

-getPageOut

-getRoEvict

-getRwEvict

-getPageTrickle

-getPageClean

-getPageDirty

-getHashBuckets

-getHashMutexes

-getPageSize

-getHashSearches

-getHashLongest

-getHashExamined

-getHashNowait

-getHashWait

-getHashMaxNowait

getCacheHit

getCacheMiss

getPageCreate

getPageIn

getPageOut

getRoEvict

getRwEvict

getPageTrickle

getPageClean

getPageDirty

getHashBuckets

getHashMutexes

getPageSize

getHashSearches

getHashLongest

getHashExamined

getHashNowait

getHashWait

getHashMaxNowait

-getHashMaxWait

-getRegionNowait

-getRegionWait

-getMultiversionFrozen

-getMultiversionThawed

-getMultiversionFreed

-getAlloc

-getAllocBuckets

-getAllocMaxBuckets

-getAllocPages

-getAllocMaxPages

-getIoWait

-getSyncInterrupted

-getRegSize

-getRegmax

-toString

getHashMaxWait

- -com.sleepycat.db -
-Class CacheStats