Respostas:
Instale o apr-util (é necessário executar ab):
yum install apr-util
Instale o yum-utils:
yum install yum-utils
Faça o download do httpd an extract:
mkdir ~/httpd
cd ~/httpd
yumdownloader httpd
rpm2cpio httpd-2.2.3-43.el5.centos.3.i386.rpm | cpio -idmv
mv usr/bin/ab /usr/bin/ab
cd ~
rm -rf ~/httpd
Execute ab:
ab http://google.ru/
This is ApacheBench, Version 2.0.40-dev <$Revision: 1.146 $> apache-2.0
pacman -S apr-util
No meu CentOS 6.2, isso funcionou:
sudo yum install httpd-tools
Isso deve ajudá-lo. Depende da biblioteca Apache Portable Runtime e da biblioteca APR-util
http://code.google.com/p/apachebench-standalone/wiki/HowToBuild