A disk cache to store expensive data on a local disk. More...

#include <UT_LocalDiskCache.h>

Public Member Functions
	UT_LocalDiskCache (const char *cache_name, int64 max_item_size, int64 max_item_count)

	~UT_LocalDiskCache ()

void	clearCache (bool reset_file=true)

bool	extractFromCache (const UT_LocalDiskCacheKey &key, void *buffer, int64 &buffer_size, bool remove_from_cache=true)

void	storeInCache (const UT_LocalDiskCacheKey &key, const void *buffer, int64 buffer_size)
	Store in the cache. More...

int64	getMemoryUsed () const
	Get memory used. More...

int64	getFileSize () const
	Get the file size. More...

template<typename T >
void	traverseCache (T &task)
	Traverse the cache. More...

const UT_CappedCache &	getCache () const
	Const access to the cache. More...

Detailed Description

A disk cache to store expensive data on a local disk.

In some cases, accessing data can be expensive:

Loading over a saturated network
An expensive computation This cache provides a means to store this data on disk. The disk file is automatically cleaned up when the program completes.

This cache makes a reasonable secondary cache.

Definition at line 47 of file UT_LocalDiskCache.h.

Constructor & Destructor Documentation

UT_LocalDiskCache::UT_LocalDiskCache	(	const char *	cache_name,
		int64	max_item_size,
		int64	max_item_count
	)

The cache is used to store data in a temporary disk file max_item_size is the maximum size for each item put into the cache max_item_count is the maximum number of items to be stored in the cache It's fairly obvious that the maximum size for the disk file will be max_item_size*max_item_count.

UT_LocalDiskCache::~UT_LocalDiskCache ( )

Member Function Documentation

void UT_LocalDiskCache::clearCache ( bool reset_file = true )

Clear entire disk cache. This is not thread safe and should only be called when the cache isn't under contention.

bool UT_LocalDiskCache::extractFromCache	(	const UT_LocalDiskCacheKey &	key,
		void *	buffer,
		int64 &	buffer_size,
		bool	remove_from_cache = `true`
	)

Extract from the disk cache. Once extracted, the item will no longer exist in the cache.

The remove_from_cache flag determines whether the object will be removed from the disk cache after extraction. Since this cache is usually used as a secondary cache, it's usually the primary cache which extracts the data from the disk cache (keeping the object in the primary cache after).

const UT_CappedCache& UT_LocalDiskCache::getCache ( ) const

inline

Const access to the cache.

Definition at line 97 of file UT_LocalDiskCache.h.

int64 UT_LocalDiskCache::getFileSize ( ) const

inline

Get the file size.

Definition at line 88 of file UT_LocalDiskCache.h.

int64 UT_LocalDiskCache::getMemoryUsed ( ) const

Get memory used.

void UT_LocalDiskCache::storeInCache	(	const UT_LocalDiskCacheKey &	key,
		const void *	buffer,
		int64	buffer_size
	)

Store in the cache.

template<typename T >

void UT_LocalDiskCache::traverseCache ( T & task )

inline

Traverse the cache.

Definition at line 91 of file UT_LocalDiskCache.h.

The documentation for this class was generated from the following file:

UT/UT_LocalDiskCache.h

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation