#include <StorageAccountProxy.h>

Inheritance diagram for StorageAccountProxy:

Public Member Functions
virtual void	close (void)
virtual void	flush (void)
virtual IOOffset	position (IOOffset offset, Relative whence=SET)
virtual bool	prefetch (const IOPosBuffer *what, IOSize n)
virtual IOSize	read (void *into, IOSize n)
virtual IOSize	read (void *into, IOSize n, IOOffset pos)
virtual IOSize	readv (IOBuffer *into, IOSize n)
virtual IOSize	readv (IOPosBuffer *into, IOSize n)
virtual void	resize (IOOffset size)
	StorageAccountProxy (const std::string &storageClass, Storage *baseStorage)
virtual IOSize	write (const void *from, IOSize n)
virtual IOSize	write (const void *from, IOSize n, IOOffset pos)
virtual IOSize	writev (const IOBuffer *from, IOSize n)
virtual IOSize	writev (const IOPosBuffer *from, IOSize n)
	~StorageAccountProxy (void)
Protected Attributes
Storage *	m_baseStorage
StorageAccount::Counter &	m_statsPosition
StorageAccount::Counter &	m_statsPrefetch
StorageAccount::Counter &	m_statsRead
StorageAccount::Counter &	m_statsReadV
StorageAccount::Counter &	m_statsWrite
StorageAccount::Counter &	m_statsWriteV
std::string	m_storageClass

Detailed Description

Proxy class that wraps SEAL's Storage class with one that ticks StorageAccount counters for significant operations. The returned Storage objects from StorageMaker are automatically wrapped with this class.

Future improvement would be to implement more methods so that the wrapper itself doesn't cause peroformance degradation if the base storage does actually implement "sophisticated" features.

Definition at line 16 of file StorageAccountProxy.h.

Constructor & Destructor Documentation

StorageAccountProxy::StorageAccountProxy	(	const std::string &	storageClass,
		Storage *	baseStorage
	)

Definition at line 3 of file StorageAccountProxy.cc.

References StorageAccount::counter(), m_storageClass, and StorageAccount::Stamp::tick().

  : m_storageClass (storageClass),
    m_baseStorage (baseStorage),
    m_statsRead (StorageAccount::counter (m_storageClass, "read")),
    m_statsReadV (StorageAccount::counter (m_storageClass, "readv")),
    m_statsWrite (StorageAccount::counter (m_storageClass, "write")),
    m_statsWriteV (StorageAccount::counter (m_storageClass, "writev")),
    m_statsPosition (StorageAccount::counter (m_storageClass, "position")),
    m_statsPrefetch (StorageAccount::counter (m_storageClass, "prefetch"))
{
  StorageAccount::Stamp stats (StorageAccount::counter (m_storageClass, "construct"));
  stats.tick ();
}

StorageAccountProxy::~StorageAccountProxy ( void )

Definition at line 18 of file StorageAccountProxy.cc.

References StorageAccount::counter(), m_baseStorage, m_storageClass, and StorageAccount::Stamp::tick().

{
  StorageAccount::Stamp stats (StorageAccount::counter (m_storageClass, "destruct"));
  delete m_baseStorage;
  stats.tick ();
}

Member Function Documentation

void StorageAccountProxy::close ( void ) [virtual]

Reimplemented from Storage.

Definition at line 123 of file StorageAccountProxy.cc.

References Storage::close(), StorageAccount::counter(), m_baseStorage, m_storageClass, and StorageAccount::Stamp::tick().

{
  StorageAccount::Stamp stats (StorageAccount::counter (m_storageClass, "close"));
  m_baseStorage->close ();
  stats.tick ();
}

void StorageAccountProxy::flush ( void ) [virtual]

Reimplemented from Storage.

Definition at line 115 of file StorageAccountProxy.cc.

References StorageAccount::counter(), Storage::flush(), m_baseStorage, m_storageClass, and StorageAccount::Stamp::tick().

{
  StorageAccount::Stamp stats (StorageAccount::counter (m_storageClass, "flush"));
  m_baseStorage->flush ();
  stats.tick ();
}

IOOffset StorageAccountProxy::position	(	IOOffset	offset,
		Relative	whence = `SET`
	)		`[virtual]`

Implements Storage.

Definition at line 98 of file StorageAccountProxy.cc.

References m_baseStorage, m_statsPosition, Storage::position(), query::result, and StorageAccount::Stamp::tick().

{
  StorageAccount::Stamp stats (m_statsPosition);
  IOOffset result = m_baseStorage->position (offset, whence);
  stats.tick ();
  return result;
}

bool StorageAccountProxy::prefetch	(	const IOPosBuffer *	what,
		IOSize	n
	)		`[virtual]`

Reimplemented from Storage.

Definition at line 131 of file StorageAccountProxy.cc.

References i, m_baseStorage, m_statsPrefetch, n, Storage::prefetch(), Storage::size(), StorageAccount::Stamp::tick(), pileupDistInMC::total, and relativeConstraints::value.

{
  StorageAccount::Stamp stats (m_statsPrefetch);
  bool value = m_baseStorage->prefetch(what, n);
  if (value)
  {
    IOSize total = 0;
    for (IOSize i = 0; i < n; ++i)
      total += what[i].size();
    stats.tick (total);
  }
  return value;
}

IOSize StorageAccountProxy::read	(	void *	into,
		IOSize	n
	)		`[virtual]`

Read into into at most n number of bytes.

If this is a blocking stream, the call will block until some data can be read, end of input is reached, or an exception is thrown. For a non-blocking stream the available input is returned. If none is available, an exception is thrown.

Returns:: The number of bytes actually read. This is less or equal to the size of the buffer. Zero indicates that the end of the input has been reached: end of file, or remote end closing for a connected channel like a pipe or a socket. Otherwise the value can be less than requested if limited amount of input is currently available for platform or implementation reasons.

Exceptions:

In	case of error, a #IOError exception is thrown. This includes the situation where the input stream is in non-blocking mode and no input is currently available (FIXME: make this simpler; clarify which exception).

Implements IOInput.

Definition at line 26 of file StorageAccountProxy.cc.

References m_baseStorage, m_statsRead, Storage::read(), query::result, and StorageAccount::Stamp::tick().

{
  StorageAccount::Stamp stats (m_statsRead);
  IOSize result = m_baseStorage->read (into, n);
  stats.tick (result);
  return result;
}

IOSize StorageAccountProxy::read	(	void *	into,
		IOSize	n,
		IOOffset	pos
	)		`[virtual]`

Reimplemented from Storage.

Definition at line 35 of file StorageAccountProxy.cc.

References m_baseStorage, m_statsRead, Storage::read(), query::result, and StorageAccount::Stamp::tick().

{
  StorageAccount::Stamp stats (m_statsRead);
  IOSize result = m_baseStorage->read (into, n, pos);
  stats.tick (result);
  return result;
}

IOSize StorageAccountProxy::readv	(	IOBuffer *	into,
		IOSize	buffers
	)		`[virtual]`

Read from the input stream into multiple scattered buffers. There are buffers to fill in an array starting at into; the memory those buffers occupy does not need to be contiguous. The buffers are filled in the order given, eac buffer is filled fully before the subsequent buffers.

If this is a blocking stream, the call will block until some data can be read, end of input is reached, or an exception is thrown. For a non-blocking stream the available input is returned. If none is available, an exception is thrown.

The base class implementation uses read(void *, IOSize) method, but derived classes may implement a more efficient alternative.

Returns:: The number of bytes actually read. This is less or equal to the size of the buffer. Zero indicates that the end of the input has been reached: end of file, or remote end closing for a connected channel like a pipe or a socket. Otherwise the value can be less than requested if limited amount of input is currently available for platform or implementation reasons. Note that the return value indicates the number of bytes read, not the number of buffers; it is the sum total of bytes filled into all the buffers.

Exceptions:

In case of error, a #IOError exception is thrown. However if some data has already been read, the error is swallowed and the method returns the data read so far. It is assumed that persistent errors will occur anyway on the next read and sporadic errors like stream becoming unvailable can be ignored. Use xread() if a different policy is desirable.

Reimplemented from IOInput.

Definition at line 44 of file StorageAccountProxy.cc.

References m_baseStorage, m_statsReadV, Storage::readv(), query::result, and StorageAccount::Stamp::tick().

{
  StorageAccount::Stamp stats (m_statsReadV);
  IOSize result = m_baseStorage->readv (into, n);
  stats.tick (result);
  return result;
}

IOSize StorageAccountProxy::readv	(	IOPosBuffer *	into,
		IOSize	n
	)		`[virtual]`

Reimplemented from Storage.

Definition at line 53 of file StorageAccountProxy.cc.

References m_baseStorage, m_statsReadV, Storage::readv(), query::result, and StorageAccount::Stamp::tick().

{
  StorageAccount::Stamp stats (m_statsReadV);
  IOSize result = m_baseStorage->readv (into, n);
  stats.tick (result);
  return result;
}

void StorageAccountProxy::resize ( IOOffset size ) [virtual]

Implements Storage.

Definition at line 107 of file StorageAccountProxy.cc.

References StorageAccount::counter(), m_baseStorage, m_storageClass, Storage::resize(), and StorageAccount::Stamp::tick().

{
  StorageAccount::Stamp stats (StorageAccount::counter (m_storageClass, "resize"));
  m_baseStorage->resize (size);
  stats.tick ();
}

IOSize StorageAccountProxy::write	(	const void *	from,
		IOSize	n,
		IOOffset	pos
	)		`[virtual]`

Reimplemented from Storage.

Definition at line 71 of file StorageAccountProxy.cc.

References m_baseStorage, m_statsWrite, query::result, StorageAccount::Stamp::tick(), and Storage::write().

{
  StorageAccount::Stamp stats (m_statsWrite);
  IOSize result = m_baseStorage->write (from, n, pos);
  stats.tick (result);
  return result;
}

IOSize StorageAccountProxy::write	(	const void *	from,
		IOSize	n
	)		`[virtual]`

Write n bytes of data starting at address from.

Returns:: The number of bytes written. Normally this will be n, but can be less, even zero, for example if the stream is non-blocking mode and cannot accept input at this time.

Exceptions:

In	case of error, an exception is thrown. However if the stream is in non-blocking mode and cannot accept output, it will not throw an exception -- the return value will be less than requested.

Implements IOOutput.

Definition at line 62 of file StorageAccountProxy.cc.

References m_baseStorage, m_statsWrite, query::result, StorageAccount::Stamp::tick(), and Storage::write().

{
  StorageAccount::Stamp stats (m_statsWrite);
  IOSize result = m_baseStorage->write (from, n);
  stats.tick (result);
  return result;
}

IOSize StorageAccountProxy::writev	(	const IOPosBuffer *	from,
		IOSize	n
	)		`[virtual]`

Reimplemented from Storage.

Definition at line 89 of file StorageAccountProxy.cc.

References m_baseStorage, m_statsWriteV, query::result, StorageAccount::Stamp::tick(), and Storage::writev().

{
  StorageAccount::Stamp stats (m_statsWriteV);
  IOSize result = m_baseStorage->writev (from, n);
  stats.tick (result);
  return result;
}

IOSize StorageAccountProxy::writev	(	const IOBuffer *	from,
		IOSize	buffers
	)		`[virtual]`

Write to the output stream from multiple buffers. There are buffers to fill in an array starting at from. The buffers are filled in the order given, each buffer fully before the subsequent buffers. The method uses write(const void *, IOSize), but may be implemented more efficiently in derived classes.

Note that derived classes should not normally call this method, as it simply routes the call back to derived class through the other virtual functions. Use this method only at the "outside edge" when transferring calls from one object to another, not in up/down calls in the inheritance tree.

Returns:: The number of bytes actually written. This is less or equal to the size of the buffers. The value can be less than requested if the stream is unable to accept all the output for platform or implementation reasons. Note that the return value indicates the number of bytes written, not the number of buffers; it is the sum total of bytes written from all the buffers.

Exceptions:

In	case of error, an exception is thrown. However if the stream is in non-blocking mode and cannot accept output, it will not throw an exception -- the return value will be less than requested.

Reimplemented from IOOutput.

Definition at line 80 of file StorageAccountProxy.cc.

References m_baseStorage, m_statsWriteV, query::result, StorageAccount::Stamp::tick(), and Storage::writev().

{
  StorageAccount::Stamp stats (m_statsWriteV);
  IOSize result = m_baseStorage->writev (from, n);
  stats.tick (result);
  return result;
}

Member Data Documentation

Storage* StorageAccountProxy::m_baseStorage [protected]

Definition at line 42 of file StorageAccountProxy.h.

Referenced by close(), flush(), position(), prefetch(), read(), readv(), resize(), write(), writev(), and ~StorageAccountProxy().

StorageAccount::Counter& StorageAccountProxy::m_statsPosition [protected]

Definition at line 48 of file StorageAccountProxy.h.

Referenced by position().

StorageAccount::Counter& StorageAccountProxy::m_statsPrefetch [protected]

Definition at line 49 of file StorageAccountProxy.h.

Referenced by prefetch().

StorageAccount::Counter& StorageAccountProxy::m_statsRead [protected]

Definition at line 44 of file StorageAccountProxy.h.

Referenced by read().

StorageAccount::Counter& StorageAccountProxy::m_statsReadV [protected]

Definition at line 45 of file StorageAccountProxy.h.

Referenced by readv().

StorageAccount::Counter& StorageAccountProxy::m_statsWrite [protected]

Definition at line 46 of file StorageAccountProxy.h.

Referenced by write().

StorageAccount::Counter& StorageAccountProxy::m_statsWriteV [protected]

Definition at line 47 of file StorageAccountProxy.h.

Referenced by writev().

std::string StorageAccountProxy::m_storageClass [protected]

Definition at line 41 of file StorageAccountProxy.h.

Referenced by close(), flush(), resize(), StorageAccountProxy(), and ~StorageAccountProxy().

StorageAccountProxy Class Reference

Public Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation