W3 Total Cache

Insights

  • Before using this, I saw page load times of 5-10 seconds. Afterwards, almost instantaneous.
  • Memory based cache did little, Disc based worked well
  • Almost the entire gain is from page caching. I saw little to no effect from the other modes.
  • This only affects public facing pages. Logged on, administrative pages are not helped.
  • Pages with content based on a table query are not updated

Comparisons

  • I compared this to WP-Optimize. This did a distinctly better job.
  • I compared this to Lightspeed. Lightspeed interface seemed less clear.

To Investigate

  • How do I improve admin pages
  • How do I force a specific page to not be cached

Process

  • Install plugin
  • Use Setup Guide to Test and configure
  • Maybe adjust using General Settings
    • Page Caching On, use Disk storage
    • Turn off object and database caching. Some commentary suggests this slows down admin functions.
  • Set Page Cacheing Settings
    • Set to pre-load, so that pages are always ready

Settings – General

  • Page Cache: Enable
  • Page Cache Method: Disk:Enhanced
  • Minify: Not enabled
  • Database Cache: NOT enabled
  • Object Cache: NOT enabled
  • Browser Cache: Enabled
  • CDN: Not enabled
  • Reverse Proxy: Not Enabled
  • Lazy Load Images: Enabled
  • Fragment Cache: Disabled
  • Miscellaneous: Disabled
  • Debug: Enable to view, otherwise disable

Settings – Page Caching

  • Don’t Cache pages for logged in Users: Disabled
  • Cache Period
    • Automatically Prime the page cache: Enabled
    • Update Interval: 900 seconds
    • Pages per interval: 10
    • Site Map URL: Fill in
    • Preload the post cache upon publish events: Enabled

Settings – Browser Caching

  • Genteral
    • Last Modified header: Enabled
    • Expires Header: Disabled
    • Cache Control Header: Enabled
    • Entity tag (Etag): Enabled
    • W3 Total Cache header: Disabled
    • Enable HTTP (gzip) compression:Enabled
  • CSS
    • Doesn’t seem to have any effect
  • HTML & XML
    • Last Modified Header: Enable
    • Cache Control Header: Enabled
    • Cache Control Policy: Cache with max-age
    • Set Entity Tag: Enabled
    • Enable HTTP Gzip compression : Enabled
  • Media and other files:
    • Set Last Modifes header:Enable
    • Set Expires header: Disabled
    • Set Cache Control Policy: Enabled
    • Cache Control Policy: Cache with Max Age
    • Set Entity Flag: Enabled
    • Enable HTTP (gzip) compression: Enabled

Test 1: Does a change affect the web page


Purge all Cache in W3 Total Cache
Load page on a browser – confirm slow first pass
Reload – confirm speed up
Change the page
Reload on the browser. It should take longer, but reflect the change

Test 2: Is there caching other than the brower


Purge all Cache in W3 Total Cache
Load Page on browser A – should be slow
Reload – should be fast
Load same page on browser B – should be fast

Test 3: Is there caching of CSS


Load Page on broswer 2x – second time should be fast
Change CSS and save
Reload Page – visual change should appear (but it does not!!!!)

Solutions: Purging all Cache will fix this.
Changing the content of a page will fix this.

Test 4: Is preloading happening


Set preload interval to 60 seconds
Purge all cache
Load page to confirm slow
Repurge cache
Wait 60 seconds
Load page – should be fast!