Profiling with Xhprof

&

it's usage with Drupal

What it does ?

• Reports function level counts and inclusive and exclusive metrics such as Wall time, CPU time & Memory usage.


• Function Profiles Can be broken down by Callers and Callees.
   
• Simple HTML based User interface to show reports.
   
• Provides Call graph view of the report.

Can be useful for...

• Understanding structure of the code being executed in the form of callers and callees.


• Provides hierarchical nature of the reports that can be used to determine the backtrace of the code.
   
• Finding out the  difference in the reports by providing the ability to compare.
   
• Can be used on production (with some things to keep in mind).

- Call Graph : Displays executed code in a visual diagram where each node corresponds to a function or method and their relations show Code Flow.

- Exclusive Time : How long does it take to execute a function without time spent on other functions/methods.

- Inclusive Time : Total time spent executing a function/method including any external call.
 

Some Basic Terminologies to understand xhprof reports better...

Flat Profile

Provides function-level summary information such as number of calls, inclusive/exclusive wall time, memory usage, and CPU time.

Hierarchical Profile

For each function, it provides a breakdown of calls and times per parent (caller) & child (callee)

Profiling with XHprof

Output