# CMAKE\_UNITY\_BUILD\_BATCH\_SIZE seens not has any effect in windows & linux

**URL:** <https://discourse.cmake.org/t/cmake-unity-build-batch-size-seens-not-has-any-effect-in-windows-linux/3761>\
**Category:** Code\
**Created:** [July 15, 2021, 8:15am UTC](https://discourse.cmake.org/t/cmake-unity-build-batch-size-seens-not-has-any-effect-in-windows-linux/3761 "2021-07-15T08:15:10Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![1112](https://discourse.cmake.org/user_avatar/discourse.cmake.org/1112/32/1637_2.png) [@1112](https://discourse.cmake.org/u/1112)\
**Post date:** [July 15, 2021, 8:15am UTC](https://discourse.cmake.org/t/cmake-unity-build-batch-size-seens-not-has-any-effect-in-windows-linux/3761/1 "2021-07-15T08:15:10Z")

</div>

Our team open the unity build in cmake, unity build is work right, but the batch size seens not have any effect for our.

test code is like:

set\_target\_properties(TableReader PROPERTIES  
UNITY\_BUILD\_MODE BATCH  
CMAKE\_UNITY\_BUILD\_BATCH\_SIZE 20  
UNITY\_BUILD ON  
)

---

<div class="post-metadata">

**Author:** ![fenrir](https://discourse.cmake.org/user_avatar/discourse.cmake.org/fenrir/32/734_2.png) [@fenrir](https://discourse.cmake.org/u/fenrir)\
**Post date:** [July 15, 2021, 8:19am UTC](https://discourse.cmake.org/t/cmake-unity-build-batch-size-seens-not-has-any-effect-in-windows-linux/3761/2 "2021-07-15T08:19:25Z")

</div>

`CMAKE_UNITY_BUILD_BATCH_SIZE` is a variable you can set on global/directory scope. It serves as a default value for `UNITY_BUILD_BATCH_SIZE` property.

You probably want:

```auto
set_target_properties(TableReader PROPERTIES
    UNITY_BUILD_MODE BATCH
    UNITY_BUILD_BATCH_SIZE 20
    UNITY_BUILD ON
)

```