---
title: "optimize | Microsoft Docs"
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---
# optimize
Specifies optimizations to be performed on a function-by-function basis.  
  
## Syntax  
  
```  
  
#pragma optimize( "[optimization-list]", {on | off} )  
```  
  
## Remarks  
 The **optimize** pragma must appear outside a function and takes effect at the first function defined after the pragma is seen. The **on** and **off** arguments turn options specified in the *optimization-list* on or off.  
  
 The *optimization-list* can be zero or more of the parameters shown in the following table.  
  
### Parameters of the optimize Pragma  
  
|Parameter(s)|Type of optimization|  
|--------------------|--------------------------|  
|**g**|Enable global optimizations.|  
|**s** or **t**|Specify short or fast sequences of machine code.|  
|**y**|Generate frame pointers on the program stack.|  
  
 These are the same letters used with the [/O](../build/reference/o-options-optimize-code.md) compiler options. For example, the following pragma is equivalent to the **/Os** compiler option:  
  
```  
#pragma optimize( "ts", on )  
```  
  
 Using the **optimize** pragma with the empty string (**""**) is a special form of the directive:  
  
 When you use the **off** parameter, it turns the optimizations, listed in the table earlier in this topic, off.  
  
 When you use the **on** parameter, it resets the optimizations to those that you specified with the [/O](../build/reference/o-options-optimize-code.md) compiler option.  
  
```  
#pragma optimize( "", off )  
.  
.  
.  
#pragma optimize( "", on )   
```  
  
## See Also  
 [Pragma Directives and the __Pragma Keyword](../preprocessor/pragma-directives-and-the-pragma-keyword.md)