Difficult to say without having details, did you had a chance to enable any rules? 
Are you ware of the Core Rule Set (CRS): 


The performance is directly related to the rules that you have enabled, you probably
want to measure with those rules, fell free to share the number with us :)


On Nov 22, 2013, at 11:14 AM, ghost 123456 <oyc1026@gmail.com>

Hello, I've just installed ModSecurity-apache-2.7.5 from source code.

After finished configuring and starting apache, I've called my page running on apache.

But, the calling speed is too slow. 

What's the problem?
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