crt-disable-perfcrit-locks.md

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_CRT_DISABLE_PERFCRIT_LOCKS | Microsoft Docs		11/04/2016			cpp-standard-libraries		article	_CRT_DISABLE_PERFCRIT_LOCKS CRT_DISABLE_PERFCRIT_LOCKS	C++	CRT_DISABLE_PERFCRIT_LOCKS constant _CRT_DISABLE_PERFCRIT_LOCKS constant	36cc2d86-cdb1-4b2b-a03c-c0d3818e7c6f	4	corob-msft	corob	ghogen

_CRT_DISABLE_PERFCRIT_LOCKS

Disables performance-critical locking in I/O operations.

Syntax

#define _CRT_DISABLE_PERFCRIT_LOCKS  

Remarks

Defining this symbol can improve performance in single-threaded I/O-bound programs by forcing all I/O operations to assume a single-threaded I/O model. For more information, see Multithreaded Libraries Performance.

See Also

Global Constants