How to investigate initial server response latency (2.9s) of wordpress/nginx site?

Question

I infer it takes roughly 3 seconds to build HTML and send it back. Is there something obvious that I am missing?

Hardware: 2 CPU, 4 GB RAM, 100 gb HDD Stack: Fresh CentOS, Nginx, Wordpress

DD perf averages 200-300 MB/s

EDIT: Getting "Unable to allocate memory for pool" PHP error in php-fpm log. Help welcome.

Answer 1

I'd start with benchmarking the wordpress install.

http://wordpress.org/plugins/benchmark/

Answer 2

As David said it's a good idea to run benchmarks, you should also take a look into slow query logs on your database. Then of course you'll want expires headers to cache the pages, and usually a good idea to have

<FilesMatch "\\.(js|css|html|htm|php|xml|eot|jpg|gif|png|jpeg)$">
SetOutputFilter DEFLATE
</FilesMatch>

inside your .htaccess or server config