Comet Cache

If you care about the speed of your site, Comet Cache is one of those plugins that you absolutely MUST have installed :-) Comet Cache takes a real-time snapshot (building a cache) of every Page, Post, Category, Link, etc. These snapshots are then stored (cached) intuitively, so they can be referenced later, in order to save all of that processing time that has been dragging your site down and costing you money.

The Comet Cache plugin uses configuration options that you select from the options panel. See: Comet Cache - Options in your Dashboard. Once a file has been cached, Comet Cache uses advanced techniques that allow it to recognize when it should and should not serve a cached version of the file. By default, Comet Cache does not serve cached pages to users who are logged in, or to users who have left comments recently. Comet Cache also excludes administrative pages, login pages, POST/PUT/DELETE/GET(w/ query string) requests and/or CLI processes.

Features

• SIMPLE and well-documented configuration (just enable and you're all set!).
• Options to control the automatic cache clearing behavior for Home and Posts Page, Author Page, Category, Tag, and Custom Term Archives, Custom Post Type Archives, RSS/RDF/ATOM Feeds, and XML Sitemaps.
• URI exclusion patterns (now supporting wildcards too).
• User-Agent exclusion patterns (now supporting wildcards too).
• HTTP referrer exclusion patterns (now supporting wildcards too).
• The ability to set an automatic expiration time for cache files.
• Client-Side Caching (to allow double-caching in the client-side browser).
• Caching for 404 requests to reduce the impact of those requests on the server.
• RSS, RDF, and Atom Feed caching.
• The ability to cache or ignore URLs that contain query strings (GET Requests).
• Apache Optimizations to enable GZIP Compression.
• WP-CLI Compatibility.
• An Advanced Cache Plugin system for theme and plugin developers.

Pro Features

• The ability to cache logged-in users too! (VERY powerful, particularly for membership sites).
• A new improved "Clear Cache" button in the admin bar (along with an option to enable/disable this feature).
• Options for Automatic and Intelligent Cache Clearing of Posts, Pages, Custom Post Types, Categories, Tags, Links, Themes, Users, and more.
• The ability to disable Dashboard notifications related to automatic clearing/purging on change detections.
• The ability to clear Markdown-related cache files generated by the s2Clean theme for WordPress (if installed).
• The ability to run custom PHP code whenever the cache is cleared.
• The ability to Auto-Clear a List of Custom URLs.
• Clear Cache User Permissions to give other users permission to clear the cache by specifying a list of Roles and/or Capabilities.
• Cache Statistics to help you gain insight into the status of your site cache.
• Import/Export functionality for Comet Cache configuration files.
• A Dynamic Version Salt (customize the caching engine).
• Multisite Host Exclusion Patterns to exclude specific child blogs from being cached in a Multisite Network.
• Mobile Mode that supports creating multiple versions of the cache for sites with adaptive designs.
• HTML Compressor to automatically combine and compresses CSS/JS/HTML code.
• Auto-Cache Engine to pre-cache your site at 15-minute intervals.
• Static CDN Filters to serve some and/or ALL static files on your site from a CDN of your choosing, including support for Multiple CDN Host Names, Domain Sharding, and WordPress Multisite Networks.
• Domain Sharding / Multiple CDN Hosts to work around concurrency limits and make it possible for browsers to download more resources simultaneously.
• Server Load Monitoring to avoid regenerating the cache while the server is very busy by specifying a maximum server load average.
• Cache Statistics and Charts to analyze statistics about the page cache, HTML Compressor cache, PHP OPCache, and server health.
• Apache Optimizations to enable web server GZIP Compression, Leverage Browser Caching, Enforce Canonical URLs, and more.
• An Automatic Updater to update Comet Cache Pro from your WordPress Dashboard.
• Compatibility with ManageWP and InfiniteWP.
• Rockstar support for all Comet Cache features.

TIP: you can preview Pro features in the free version by clicking the "Preview Pro Features" link at the top of your Comet Cache options.