Magento - Profiling
A feature called Profiler that plays an important role in Magento development and can be used for debugging. It specifies blocks of code that slow down page loading. The Magento Profiler reports the time it took a block of code to execute, the number of times the block of code was executed, and the memory it used when rendering a Magento web page.
To enable Profiler , do the following:
Step 1 - Login to your Magento admin panel.
Step 2 − Go to the system menu and click on the configuration option .
Step 3 − From the left side of the navigation bar, go to the Advanced section and click on Developer .
Step 4 − Expand the Debug panel and enable the profiler by setting it to Yes and click the Save Configuration button .
Step 5 − At this point the profiler is enabled, but you need to tell the profiler which profile to which. So go to the root index.php file of your Magento installation and look for the line #Varien_Profiler::enable(); and uncomment it, i.e. remove the hash sign.
Step 6 − Now go to any of your pages, you should see the result in the footer area of the page as shown in the next screen.