While making a cfhttp call to a coldfusion server the apache httpclient library tries to generate a secure random number. It is an operation which depends on the "entropy" of the system.
In case of linux systems (mainly the ones which are freshly installed) it is observed that this operation can be quite time consuming because the system "entropy" is apparently quite low. Hence, as a consequence cfhttp calls will be slow.
Fortunately for people who deploy Coldfusion-10 on linux machines this is not a reason to worry. Just do one of the following:
1. Set this system property to your JVM – if you are using standalone CF installation, you would set it in jvm.config.
2. In $JAVA_HOME/jre/lib/security/java.security file, change the value of securerandom.source to file:/dev/./urandom
You can also refer to this post by Shilpi, from the ColdFusion team which talks about this issue