com.bigdata.journal
Class DiskOnlyStrategy.StoreCounters

java.lang.Object
  com.bigdata.journal.DiskOnlyStrategy.StoreCounters

Enclosing class:

DiskOnlyStrategy

public static class DiskOnlyStrategy.StoreCounters
extends Object

Counters for IRawStore access, including operations that read or write through to the underlying media.

Version:

$Id: DiskOnlyStrategy.java 2265 2009-10-26 12:51:06Z thompsonbry $

Author:

Bryan Thompson

TODO:

report elapsed time and average latency for force, reopen, and writeRootBlock., counters need to be atomic if we want to avoid the possibility of concurrent x++ operations failing to correctly increment x for each request.

Field Summary

long	bytesRead #of bytes read.
long	bytesReadFromDisk #of bytes that have been read from the disk.
long	bytesWritten #of bytes written.
long	bytesWrittenOnDisk #of bytes that have been written on the disk.
long	elapsedCacheReadNanos Total elapsed time checking the disk write cache for records to be read.
long	elapsedCacheWriteNanos Total elapsed time writing records into the cache (does not count time to flush the cache when it is full or to write records that do not fit in the cache directly to the disk).
long	elapsedDiskReadNanos Total elapsed time for reading on the disk.
long	elapsedDiskWriteNanos Total elapsed time for writing on the disk.
long	elapsedReadNanos Total elapsed time for reads.
long	elapsedWriteNanos Total elapsed time for writes.
long	maxReadSize The size of the largest record read.
long	maxWriteSize The size of the largest record written.
long	ncacheFlush #of times the write cache was flushed to disk.
long	ncacheRead #of read requests that are satisfied by our write cache (vs the OS or disk level write cache).
long	ncacheWrite #of write requests that are absorbed by our write cache (vs the OS or disk level write cache).
long	ndiskRead #of read requests that read through to the backing file.
long	ndiskWrite #of write requests that write through to the backing file.
long	nforce #of times the data were forced to the disk.
long	nreads #of read requests.
long	nreopen #of times the file has been reopened after it was closed by an interrupt.
long	ntruncate #of times the length of the file was changed (typically, extended).
long	nwriteRootBlock #of times one of the root blocks has been written.
long	nwrites #of write requests.

Constructor Summary

DiskOnlyStrategy.StoreCounters()
Initialize a new set of counters.

DiskOnlyStrategy.StoreCounters(DiskOnlyStrategy.StoreCounters o)
Copy ctor.

Method Summary

void	add(DiskOnlyStrategy.StoreCounters o) Adds counters to the current counters.
CounterSet	getCounters()
DiskOnlyStrategy.StoreCounters	subtract(DiskOnlyStrategy.StoreCounters o) Returns a new DiskOnlyStrategy.StoreCounters containing the current counter values minus the given counter values.
String	toString() Human readable representation of the counters.

Methods inherited from class java.lang.Object

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

Field Detail

nreads

public long nreads

#of read requests.

ncacheRead

public long ncacheRead

#of read requests that are satisfied by our write cache (vs the OS or disk level write cache).

ndiskRead

public long ndiskRead

#of read requests that read through to the backing file.

bytesRead

public long bytesRead

#of bytes read.

bytesReadFromDisk

public long bytesReadFromDisk

#of bytes that have been read from the disk.

maxReadSize

public long maxReadSize

The size of the largest record read.

elapsedReadNanos

public long elapsedReadNanos

Total elapsed time for reads.

elapsedCacheReadNanos

public long elapsedCacheReadNanos

Total elapsed time checking the disk write cache for records to be read.

elapsedDiskReadNanos

public long elapsedDiskReadNanos

Total elapsed time for reading on the disk.

nwrites

public long nwrites

#of write requests.

ncacheWrite

public long ncacheWrite

#of write requests that are absorbed by our write cache (vs the OS or disk level write cache).

ncacheFlush

public long ncacheFlush

#of times the write cache was flushed to disk.

ndiskWrite

public long ndiskWrite

#of write requests that write through to the backing file.

maxWriteSize

public long maxWriteSize

The size of the largest record written.

bytesWritten

public long bytesWritten

#of bytes written.

bytesWrittenOnDisk

public long bytesWrittenOnDisk

#of bytes that have been written on the disk.

elapsedWriteNanos

public long elapsedWriteNanos

Total elapsed time for writes.

elapsedCacheWriteNanos

public long elapsedCacheWriteNanos

Total elapsed time writing records into the cache (does not count time to flush the cache when it is full or to write records that do not fit in the cache directly to the disk).

elapsedDiskWriteNanos

public long elapsedDiskWriteNanos

Total elapsed time for writing on the disk.

nforce

public long nforce

#of times the data were forced to the disk.

ntruncate

public long ntruncate

#of times the length of the file was changed (typically, extended).

nreopen

public long nreopen

#of times the file has been reopened after it was closed by an interrupt.

nwriteRootBlock

public long nwriteRootBlock

#of times one of the root blocks has been written.

Constructor Detail

DiskOnlyStrategy.StoreCounters

public DiskOnlyStrategy.StoreCounters()

Initialize a new set of counters.

DiskOnlyStrategy.StoreCounters

public DiskOnlyStrategy.StoreCounters(DiskOnlyStrategy.StoreCounters o)

Copy ctor.

Parameters:

o -

Method Detail

add

public void add(DiskOnlyStrategy.StoreCounters o)

Adds counters to the current counters.

Parameters:

o -

subtract

public DiskOnlyStrategy.StoreCounters subtract(DiskOnlyStrategy.StoreCounters o)

Returns a new DiskOnlyStrategy.StoreCounters containing the current counter values minus the given counter values.

Parameters:

o -

Returns:

getCounters

public CounterSet getCounters()

toString

public String toString()

Human readable representation of the counters.

Overrides:

toString in class Object