Apache memory hog problem

I just recently added WordPress and PHP 5 to my server which already has Apache 2 on it. The php_sapi_name() function returns a value of “apache2handler” which I think means that PHP is set up as DSO module for Apache.

However I noticed that httpd processes became memory hog when I access the blog. Prior to accessing the blog, there are 13 httpd processes (# of processes stayed constant with subsequent access to the blog).

1st access to the blog
free shows addtl 5MB being used of buffers/cache and top shows one of the httpd process (pid 7673) resident memory jumped to 17MB from 5MB.

2nd access to the blog
free shows addtl 7MB being used of buffers/cache and top shows a different httpd process (pid 7670) resident memory jumped to 16MB from 5MB. The httpd process (pid 7673) from the 1st access stays constant at 17MB resident memory.

3rd access to the blog
free shows addtl 6MB being used of buffers/cache and top shows a yet different httpd process (pid 7677) resident memory jumped to 16MB from 5MB. The other 2 httpd processes (pid 7673, 7670) stay constant at 17MB & 16MB resident memory.

All the blog access above is just launching the default wordpress blog initial page and subsequent accesses refresh the same page. This is definitely a pattern. Every blog page access causes one of the httpd process to increase its resident memory by 11 to 12 MB. This is the cause of the heaving swapping later on. The question is this normal behavior for a properly setup Apache / PHP / WordPress installation or is there some other configuration I can tweak?