Best Practice for PHP page memory usage?

[random1]

I have some simple test code:

 

echo memory_get_usage(true);
echo("\n" . '<br />' . "\n");
echo memory_get_usage(false);
echo("\n" . '<br />' . "\n");
echo memory_get_peak_usage();

 

that prints out the three types of memory usage in bytes for my basic admin page.

 

All three values are around 2.25 MB in bytes.

 

What's best practice for PHP memory usage? Is 2.25MB far too much for a single user's visit?

 

Do these PHP memory values include images in the page?