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2.3.12.2.5 Allocate

  • Article

The Allocate structure describes cluster allocation patterns in NTFS. The cache refers to in-memory structures that allow quick lookups of free cluster runs either by logical cluster number (LCN) or by run length.

The Allocate structure is as follows.


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Calls

Clusters

Hints

RunsReturned

HintsHonored

HintsClusters

Cache

CacheClusters

CacheMiss

CacheMissClusters

Calls (4 bytes): A 32-bit unsigned integer value containing the number of individual calls to allocate clusters.

Clusters (4 bytes): A 32-bit unsigned integer value containing the number of clusters allocated.

Hints (4 bytes): A 32-bit unsigned integer value containing the number of times a hint was specified when trying to determine which clusters to allocate.

RunsReturned (4 bytes): A 32-bit unsigned integer value containing the number of runs used to satisfy all the requests.

HintsHonored (4 bytes): A 32-bit unsigned integer value containing the number of times the starting LCN hint was used to determine which clusters to allocate.

HintsClusters (4 bytes): A 32-bit unsigned integer value containing the number of clusters allocated via the starting LCN hint.

Cache (4 bytes): A 32-bit unsigned integer value containing the number of times the run length cache was useful.

CacheClusters (4 bytes): A 32-bit unsigned integer value containing the number of clusters allocated via the run length cache.

CacheMiss (4 bytes): A 32-bit unsigned integer value containing the number of times the cache was not useful and the bitmapped had to be scanned for free clusters.

CacheMissClusters (4 bytes): A 32-bit unsigned integer value containing the number of clusters allocated by scanning the bitmap.