How to Enable profiling to check file loading time in theme or to test file download speed to optimize page speed in Magento 2 ?

Enable profiling (MAGE_PROFILER)

Magento profiling enables you to:

• Enable a built-in profiler.You can use a built-in profiler with Magento to perform tasks such as analyzing performance. The nature of profiling depends on the analytical tools you use. We support multiple formats, including HTML. When you enable the profiler, a var/profiler.flag file generates indicating the profiler is enabled and configurations. When disabled, this file is deleted.
• Display dependency graphs on a Magento page. A dependency graph is a list of object dependencies and all of their dependencies, and all the dependencies for those dependencies, and so on.You should be particularly interested in the list of unused dependencies, which are objects that were created because they were requested in some constructor, but were never used (that is, none of their methods were called). As a result, processor time and memory spent to create these dependencies are wasted.

Magento provides the base functionality in Magento\Framework\Profiler.

You can enable and configure the profiler using a MAGE_PROFILER variable or the command line.

Set MAGE_PROFILER

You can set the value of  MAGE_PROFILE in any of the ways discussed in Set the value of bootstrap parameters.

MAGE_PROFILE supports the following values:

• to enable a specific profiler’s output.

You can also use one of the following values to enable a specific profiler:

• csvfile which uses Magento\Framework\Profiler\Driver\Standard\Output\Csvfile
• Any other value (except 2), including an empty value, which uses Magento\Framework\Profiler\Driver\Standard\Output\Html

• to enable dependency graphs.

Dependency graphs typically display at the bottom of a page. The following figure shows portion of the output:

CLI commands

You can enable or disable the profiler using CLI commands:

php bin/magento dev:profiler:enable <type> enables the profiler with type of html (default) or csvfile

When enabled, a flagfilevar/profiler.flag is created.

dev:profiler:disable disables the profiler. When disabled, the flagfile var/profiler.flag is removed.

To enable dependency graphs, use the variable option.

To enable or disable the profiler:

1. Log in to your Magento server.
2. Change to your Magento installation directory.
3. As the file system owner, enter the following command to configure the profiler:To enable the profiler using type html and create a flagfile:

php bin/magento dev:profiler:enable html

To enable the profiler using type csvfile and create a flagfile:

php bin/magento dev:profiler:enable csvfile

The output will be saved to <project_root>/var/log/profiler.csv.

The profiler.csv will be overridden on each page refresh.

To disable the profiler and remove the flagfile:

php bin/magento dev:profiler:disable

Hope this article will help you, please leave a comment if you have any reviews or suggestions under the article.

Anything you need support from Magento 2 feel free to contact us at Alothemes and Email: support@alothemes.com