MPSState(3)            MetalPerformanceShaders.framework           MPSState(3)

NAME

       MPSState

SYNOPSIS

       #import <MPSState.h>

       Inherits NSObject.

       Inherited by MPSCNNConvolutionState, MPSRNNRecurrentImageState, and
       MPSRNNRecurrentMatrixState.

   Instance Methods
       (nullable instancetype) - init

   Properties
       NSUInteger readCount
       BOOL isTemporary
       NSString * label

Detailed Description

       This depends on Metal Framework  An opaque data container for large
       storage in MPS CNN filters  Some MPS CNN kernels produce additional
       information beyond a MPSImage. These may be pooling indices where the
       result came from, convolution weights, or other information not
       contained in the usual MPSImage result from a MPSCNNKernel. A MPSState
       object typically contains one or more expensive MTLResources such as
       textures or buffers to store this information. It provides a base class
       with interfaces for managing this storage. Child classes may add
       additional functionality specific to their contents.

       Some MPSState objects are temporary. Temporary state objects, like
       MPSTemporaryImages and Matrices, are for very short lived storage,
       perhaps just a few lines of code within the scope of a single
       MTLCommandBuffer. They are very efficient for storage, as several
       temporary objects can share the same memory over the course of a
       MTLCommandBuffer. This can improve both memory usage and time spent in
       the kernel wiring down memory and such. You may find that some large
       CNN tasks can not be computed without them, as non-temporary storage
       would simply take up too much memory.

       In exchange, the lifetime of the underlying storage in temporary
       MPSState objects needs to be carefully managed. ARC often waits until
       the end of scope to release objects. Temporary storage often needs to
       be released sooner than that. Consequently the lifetime of the data in
       the underlying MTLResources is managed by a readCount property. Each
       time a MPSCNNKernel reads a temporary MPSState object the readCount is
       automatically decremented. When it reaches zero, the underlying storage
       is recycled for use by other MPS temporary objects, and the data is
       becomes undefined. If you need to consume the data multiple times, you
       should set the readCount to a larger number to prevent the data from
       becomming undefined. You may set the readCount to 0 yourself to return
       the storage to MPS, if for any reason, you realize that the MPSState
       object will no longer be used.

       The contents of a temporary MPSState object are only valid from
       creation to the time the readCount reaches 0. The data is only valid
       for the MTLCommandBuffer on which it was created. Non-temporary
       MPSState objects are valid on any MTLCommandBuffer on the same device
       until they are released.

Method Documentation

   - (nullable instancetype) init

Property Documentation

   - (BOOL) isTemporary [read],  [nonatomic],  [assign]
   - label [read],  [write],  [atomic],  [copy]
       A string to help identify this object.

   - (NSUInteger) readCount [read],  [write],  [nonatomic],  [assign]

Author

       Generated automatically by Doxygen for
       MetalPerformanceShaders.framework from the source code.





Version MetalPerformanceShaders-Thu2Jul 13 2017                    MPSState(3)


Mac OS X 10.12.6 - Generated Tue Oct 31 19:57:06 CDT 2017