eG Monitoring
 

Measures reported by CtxNsFEOTest

The HTTP protocols that underlie web applications were originally developed to support the transmission and rendering of simple webpages. New technologies such as JavaScript and cascading style sheets (CSS), and new media types such as Flash videos and graphics-rich images, place heavy demands on front-end performance, that is, on performance at the browser level.

The Citrix ADC front end optimization (FEO) feature addresses such issues and reduces the load time and render time of webpages by:

  • Reducing the number of requests;

  • Reducing the number of bytes required for rendering each page.

  • Reducing the number of bytes in page responses.

  • Simplifying and optimizing the content served to the client browser.

Citrix ADCs support numerous web content optimizations for both desktop and mobile users. These optimizations include inlining, minification, image optimization, repositioning, and connection management. To ascertain the effectiveness of these optimizations, administrators can periodically run this test, measure how many optimizations of what types were applied in the recent past and how much data was saved in the process.

Outputs of the test: One set of results for the Citrix ADC being monitored

The measures made by this test are as follows:

Measurement Description Measurement Unit Interpretation
Imgs_resized Indicates the number of resized images during the last measurement period. Number

Image optimization reduces the image to the size indicated in the image tag by Citrix ADC, enabling client browsers to load images faster.

Gifs_to_pngs Indicates the number of images that were converted from GIF to PNG format during the last measurement period. Number

 

Jpegs_optimized Indicates the number of JPEG images that were optimized during the last measurement period. Number

JPEG optimization removes non-image data, such as comments, from JPEG images.

Imgs_to_webp Indicates the number of images that were converted to webp format. Number

This optimization converts JPEG, GIF, PNG image formats to WEBP format.

Imgs_to_jpegxr Indicates the number of images that were converted to JXR format. Number

 

Css_minifed Indicates the total number of CSS files that were minified during the last measurement period. Number

To minify a CSS file is to remove comments and whitespaces from that CSS file.

Js_minifed Indicates the total number of JavaScript files that were minified during the last measurement period. Number

To minify a JS file is to remove comments and whitespaces from that JS file.

Css_moved Indicates the number of CSS files that were moved to tag in the last measurement period. Number

You can move any CSS file present within the body tag of an HTML page to the head tag to reduce page rendering time.

Js_moved Indicates the number of JS files that were moved to the end during the last measurement period. Number

You can move any JavaScript file present in the body tag to the end of the body tag to optimize page rendering.

Import_to_links Indicates the number of CSS imports converted to links during the last measurement period. Number

A non-zero value for this measure indicates that one/more CSS import statements have been converted to HTML link tags.

Css_combined Indicates the total number of CSS combined during the last measurement period. Number

A non-zero value for this measure indicates that one/more CSS files have been combined into one file.

Cache_extended Indicates the number of objects cache extended during the last measurement period. Number

The value of this measure will be incremented if one/more cached objects are configured to be used by the browser for an extended period of time.

Http_comments_removed Indicates the number of HTML comments that were removed during the last measurement period. Number

 

Data_savings Indicates the total data savings in the last measurement period. MB

A high value for this measure indicates that the optimizations in place are effective. Therefore, a high value is desired for this measure.

Inlined_imgs Indicates the total number of inlined images in HTML during the last measurement period. Number

A non-zero value is reported by this measure if one/more inline images less than 2KB in size are found in HTML.

Inlined_css Indicates the number of inlined CSS files during the last measurement period. Number

A non-zero value is reported by this measure if one/more CSS files, whose size is less than 2KB, are found within the main page.

Inlined_js Indicates the number of inlined JS files in the last measurement period. Number

The value of this measure is incremented if one/more linked JavaScript files (less than 2KB) are converted to inline JavaScript files.

Inlined_imgs_in_css Indicates the number of inlined images in CSS during the last measurement period. Number

If one/more inline small images (less than 2KB) are referred within CSS files as background-URLs, then the value of this measure will be incremented.

Uri_replaced Indicates the total number of URIs that were replaced during the last measurement period. Number

 

Imgs_lazy_loaded Indicates the number of images that were loaded lazily during the last measurement period. Number

Lazy load images are those that are downloaded only when the user scrolls the page to view them.

Domain_sharded Indicates how many images in the last measurement period have a domain that has been set from shards. Number

 

Orig_cache_objects Indicates the number of original cache objects that were ready to be served during the last measurement period. Number

 

Opt_cache_objects Indicates the number of optimized cache objects ready to be served during the last measurement period. Number

If the value of this measure is equal to or very close to that of the Original cache objects measure, it means that the optimization techniques applied are effective.