# A question

**URL:** <https://www.ruby-forum.com/t/a-question/215906>\
**Category:** NGINX\
**Created:** [January 19, 2012, 8:06am UTC](https://www.ruby-forum.com/t/a-question/215906 "2012-01-19T08:06:09Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![luislavena](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/0ea827/32.png) [@luislavena](https://www.ruby-forum.com/u/luislavena)\
**Post date:** [January 19, 2012, 8:06am UTC](https://www.ruby-forum.com/t/a-question/215906/1 "2012-01-19T08:06:09Z")

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I want to know.  
In source code#define NGX\_MAX\_ALLOC\_FROM\_POOL (ngx\_pagesize - 1)  
Why decrement?

xujiecq