DSTORAGE_PRIORITY

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Priority levels of a DirectStorage queue.

Syntax

enum DSTORAGE_PRIORITY  : INT8  
{  
    DSTORAGE_PRIORITY_LOW = -1,  
    DSTORAGE_PRIORITY_NORMAL = 0,  
    DSTORAGE_PRIORITY_HIGH = 1,  
    DSTORAGE_PRIORITY_REALTIME = 2,  
    DSTORAGE_PRIORITY_FIRST = DSTORAGE_PRIORITY_LOW,  
    DSTORAGE_PRIORITY_LAST = DSTORAGE_PRIORITY_REALTIME,  
    DSTORAGE_PRIORITY_COUNT = 4  
}

Constants

Constant Description
DSTORAGE_PRIORITY_LOW Lowest priority for a DirectStorage operation.
DSTORAGE_PRIORITY_NORMAL Majority of requests should be at this priority.
DSTORAGE_PRIORITY_HIGH Highest priority for a DirectStorage operation.
DSTORAGE_PRIORITY_REALTIME Same priority as DSTORAGE_PRIORITY_HIGH but minimizes latency at the cost of increased CPU load.
DSTORAGE_PRIORITY_FIRST The lowest priority level; equal to DSTORAGE_PRIORITY_LOW.
DSTORAGE_PRIORITY_LAST The highest priority level; equal to DSTORAGE_PRIORITY_REALTIME.
DSTORAGE_PRIORITY_COUNT The number of priority levels.

Remarks

This enumeration is used in the DSTORAGE_QUEUE_DESC structure.

Priority is enforced by a weighted round-robin algorithm that is based on size of the requests. The difference between DSTORAGE_PRIORITY_LOW and DSTORAGE_PRIORITY_NORMAL is approximately an order of magnitude, as is the difference between DSTORAGE_PRIORITY_NORMAL and DSTORAGE_PRIORITY_HIGH.

All Win32 requests have normal priority (DSTORAGE_PRIORITY_NORMAL).

To iterate over the priority levels, use DSTORAGE_PRIORITY_FIRST, DSTORAGE_PRIORITY_LAST, and DSTORAGE_PRIORITY_COUNT.

For more information, see the "Priority" section of DirectStorage Overview.

Requirements

Header: dstorage_xs.h

Supported platforms: Xbox Series consoles

See also

DStorage