> ## Documentation Index
> Fetch the complete documentation index at: https://docs.abbyy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# MultiProcessingParams Object (IMultiProcessingParams Interface)

<Note>
  This object is implemented in FRE for Linux and Windows.
</Note>

This object provides access to the parameters of multiprocessing and multiple CPU cores usage. The main parameter which defines whether multiprocessing is to be used is the MultiProcessingMode property. All other properties regulate the number of processes and CPU cores and are taken into account only if the MultiProcessingMode property is set to MPM\_Auto or MPM\_Parallel.

<table><thead><tr><th><p><strong>Name</strong></p></th><th><p><strong>Type</strong></p></th><th><p><strong>Description</strong></p></th></tr></thead>
<tbody><tr><td><p><strong>Application</strong></p></td><td><p><strong><a href="/fine-reader/engine/api-reference/engine-object-iengine-interface">Engine</a></strong>, <a href="/fine-reader/engine/guided-tour/advanced-techniques/programming-aspects/working-with-properties#readonly_properties">read-only</a></p></td><td><p>Returns the <strong>Engine</strong> object.</p></td></tr>
<tr><td><p><a name="multiprocessingmode" /><strong>MultiProcessingMode</strong></p></td><td><p><strong><a href="/fine-reader/engine/api-reference/enumerations/multiprocessingmodeenum">MultiProcessingModeEnum</a></strong></p></td><td><p>Specifies whether ABBYY FineReader Engine should distribute processing of multi-page documents to CPU cores. The maximum number of processes which can be run is limited by the <strong>RecognitionProcessesCount</strong> property.</p><p>By default, the property is set to MPM\_Auto</p><Note>For Windows, if the engine is created with <a href="/fine-reader/engine/api-reference/functions/initializeengine-function">InitializeEngine</a>, and to MPM\_Sequential if you use <a href="/fine-reader/engine/api-reference/engine-loaders/inprocloader">InprocLoader</a> or <a href="/fine-reader/engine/api-reference/engine-loaders/outprocloader">OutprocLoader</a></Note></td></tr>
<tr><td><p><a name="processpdfinonethread" /><strong>ProcessPdfInOneThread</strong></p></td><td><p><strong><a href="/fine-reader/engine/guided-tour/advanced-techniques/programming-aspects/working-with-properties">VARIANT\_BOOL</a></strong></p></td><td><p>This property is deprecated and will be deleted in future versions.</p></td></tr>
<tr><td><p><a name="recognitionprocessescount" /><strong>RecognitionProcessesCount</strong></p></td><td><p><strong><a href="/fine-reader/engine/guided-tour/advanced-techniques/programming-aspects/working-with-properties">int</a></strong></p></td><td><p>Specifies the maximum number of processes which can be run simultaneously.</p><p>By default, this property is 0 which means that the number of processes will be equal to the minimum of the following values:</p><ul><li>number of available CPU cores<ul><li>In Windows: physical or logical CPU cores  depending on the value of the <strong>UseOnlyPhysicalCPUCores</strong> property</li></ul></li><li>number of free CPU cores available in the license,</li><li>number of pages in the document which is being processed.</li></ul><p>If you change the value of this property, ABBYY FineReader Engine immediately allocates CPU cores of the license and loads the <a href="/fine-reader/engine/api-reference/engine-object-iengine-interface/supplementary-methods/loadmodule-method">FineReader Engine Processor</a> module. If the value of this property is 0, CPU cores allocation and loading of the FineReader Engine Processor module will be performed when it is necessary.</p></td></tr><tr><td><p><a name="sharedcpucoresmask" /><strong>SharedCPUCoresMask</strong></p></td><td><p><strong><a href="/fine-reader/engine/guided-tour/advanced-techniques/programming-aspects/working-with-properties">\_\_int64</a></strong></p></td><td><p>Specifies the physical CPU cores which can be used in shared mode of CPU cores usage, as an affinity mask. Note that only physical CPU cores are masked, but not logical. The property makes sense only if CPU cores are used in shared mode (the <em>IsSharedCPUCoresMode </em>parameter of the <strong><a href="/fine-reader/engine/api-reference/functions/initializeengine-function">InitializeEngine</a></strong> function was set to TRUE during initialization).</p><p>By default, all detected CPU cores are used.</p></td></tr>
<tr><td><p><a name="useonlyphysicalcpucores" /><strong>UseOnlyPhysicalCPUCores</strong></p></td><td><p><strong><a href="/fine-reader/engine/guided-tour/advanced-techniques/programming-aspects/working-with-properties">VARIANT\_BOOL</a></strong></p></td><td><Note>The value of this property is ignored in ABBYY FineReader Engine for Linux .</Note><p>Specifies whether only physical CPU cores or physical and logical CPU cores are used during processing. This property makes sense only if the value of the <strong>RecognitionProcessesCount</strong> property is 0.</p><p>By default, the property is set to TRUE, which means that only physical CPU cores are used.</p></td></tr>
<tr><td><p><a name="customtmpfsrootpath" /><strong>CustomTmpfsRootPath</strong></p></td><td><p><strong><a href="/fine-reader/engine/guided-tour/advanced-techniques/programming-aspects/working-with-properties">BSTR</a></strong></p></td><td><p>Set a custom value for the tmpfs path.</p><p>Changing the default tmpfs path (e.g., /dev/shm) is only supported on Linux systems and may negatively impact performance.<br />If a regular filesystem is used instead of tmpfs, private data may persist on disk.</p></td></tr>
<tr><td><p><a name="usecustomtmpfsrootpath" /><strong>UseCustomTmpfsRootPath</strong></p></td><td><p><strong><a href="/fine-reader/engine/guided-tour/advanced-techniques/programming-aspects/working-with-properties">VARIANT\_BOOL</a></strong></p></td><td><p>Enables the use of a custom tmpfs path.</p><p>Changing the default tmpfs path (e.g., /dev/shm) is only supported on Linux systems and may negatively impact performance.<br />If a regular filesystem is used instead of tmpfs, private data may persist on disk.</p></td></tr></tbody></table>

## Related objects

<Tip>
  <Tip>
    [](/fine-reader/engine/api-reference/engine-object-iengine-interface/properties#multiprocessingparams)[](/fine-reader/engine/api-reference/engine-object-iengine-interface)
  </Tip>
</Tip>

[Object Diagram](/fine-reader/engine/api-reference/object-diagram)

## Samples

The object is used in the following code samples:

* Linux: [CommandLineInterface](/fine-reader/engine/guided-tour/samples#commandlineinterface)
* Windows: [CommandLineInterface](/fine-reader/engine/guided-tour/samples#commandlineinterface); and demo tools: [BatchProcessingRecognition](/fine-reader/engine/guided-tour/samples#batchprocessingrecognition), [MultiProcessingRecognition](/fine-reader/engine/guided-tour/samples#multiprocessingrecognition), [User Pattern Training Utility](/fine-reader/engine/guided-tour/samples#user_pattern_training_utility)

## See also

[Parallel Processing with ABBYY FineReader Engine](/fine-reader/engine/guided-tour/advanced-techniques/parallel-processing)

[Properties of the Engine Object](/fine-reader/engine/api-reference/engine-object-iengine-interface/properties)

[Working with Properties](/fine-reader/engine/guided-tour/advanced-techniques/programming-aspects/working-with-properties)

[Running FRE for Linux with Shared Memory size limitations](/fine-reader/engine/distribution/distribution-linux/running-fre-12-with-limited-shm)