WRITE_CACHE_TYPE enumeration (winioctl.h)

Specifies the cache type.

Syntax

typedef enum _WRITE_CACHE_TYPE {
  WriteCacheTypeUnknown,
  WriteCacheTypeNone,
  WriteCacheTypeWriteBack,
  WriteCacheTypeWriteThrough
} WRITE_CACHE_TYPE;

Constants

 
WriteCacheTypeUnknown
The system cannot report the type of the write cache.
WriteCacheTypeNone
The device does not have a write cache.
WriteCacheTypeWriteBack
The device has a write-back cache.
WriteCacheTypeWriteThrough
The device has a write-through cache.

Remarks

There are two main types of write cache: write back and write through. With a write-back cache, the device does not copy cache data to nonvolatile media until absolutely necessary. This type of operation improves the performance of write operations. With a write-through cache, the device writes data to the cache and the media in parallel. This type of operation does not improve write performance, but it makes subsequent read operations faster.

The IOCTL_STORAGE_QUERY_PROPERTY control code reports a WRITE_CACHE_TYPE value in the STORAGE_WRITE_CACHE_PROPERTY structure.

Requirements

   
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2008 [desktop apps only]
Header winioctl.h

See also