Client: Make my site load at lightning speed!
Developers: It will take time; there are several features on the site and a lot of content
Client: I want pages to load quicker.
Isn’t this ask familiar? Every client expects and demands their website to launch faster, and nothing wrong with it. There are a various methods to tackle this situation. To name a few:
(I) Cache everything
Drupal maintenance support plans is inherently equipped with caching. Caching speeds up page load time considerably.
It essentially caches anonymous pages and allows memcache enablement for authenticated users. Aggregating CSS and JS, caching the blocks and the anonymous pages; significantly improves the site load time.
This standard caching method is known to be a good solution for slow loading sites if the number of users is low. However, over a period of time, number of concurrent users increase. This significantly impacts the site’s performance, and the number of failed requests starts piling up!
The immediate recommendation from any developer would be to tweak the existing servers or replicate the servers and shop for dedicated load balancers. This results in complex setup and significant increase in infrastructure cost.
A better and cost effective solution is to use Varnish Cache. It is a web application server that significantly facilitates high performance for websites.
(II) Implement Varnish Cache
Varnish acts as a caching layer between user and backend of the site. It stores a copy of the page served by the web server when a visitor accesses a page for the first time, so that next time they access that same page, Varnish will simply serve the copy directly from its cache instead of the web server having to do it. Naturally, this takes a big load off from the server. Response times become faster, and the server is freed up to serve more requests per second.
HOW DOES VARNISH HELP TO SPEED UP YOUR WEBSITE?
a. Enhanced Performance
Varnish not only speeds up your website by caching a copy of a page served by the web server. It also ensures that your web servers need to handle less traffic which in turn improves your website’s performance and scalability. It also provides an enriched experience to the customers, with a faster and reliable website.
From an implementation perspective, Varnish offers flexibility with the Varnish Configuration Language, ease of extended functionality (Varnish Modules), content compression, etc.
b. Load balancing
Varnish can also acts as a powerful HTTP load balancer (reverse proxy), which can be used when there are more than one origin server. It can efficiently distribute incoming network traffic across a group of backend servers. This makes websites to serve hundreds of thousands of requests from users or clients and respond with the appropriate matter in a fast and reliable way.
Varnish routes the client/users requests across all servers capable of fulfilling those requests in a manner that maximizes the speed and utilization.It can also act as a failover server: If a single server goes down, the load balancer then redirects the traffic to the operational servers.
Varnish supports load balancing using both the methods i.e. round robin as well as random director. Both are available with a per-backend weighting. A basic health check of backend is also available to quickly and consistently evaluate the status of load balancing.
c. Edge Side Includes (ESI)
Varnish supports ESI. ESI are tags that are placed into HTML that helps include fragments in your pages such as Server Side Includes (SSI) or PHP include statements. ESI enables you to decide the cache policy for each fragment individually.. It can be used on your pages, directing Varnish to cache an include for a shorter time than the main document, or even not cache the include at all.
WHO BENEFITS FROM USING VARNISH?
Varnish is beneficial for businesses that value security, and who rely on their online presence for revenue. It improves user experience and customer conversion, through speed, scalability and security. It not only enhances website performance but also maximizes the bottom line of your business.
Conclusion
Varnish is an open source HTTP reverse proxy accelerator. You install it in front of any server that speaks HTTP and configure it to cache the content. Varnish Cache is really, really fast. It typically speeds up delivery with a factor of 300 – 1000x, depending on your architecture.
Varnish is used by high-profile, high-traffic websites including Wikipedia, online newspaper sites such as The New York Times, The Guardian, The Hindu, Corriere della Sera, social media and content sites such as Facebook, Twitter, Vimeo, and Tumblr. Of the Top 10K sites, around a 1/10th use this software.
Source: New feed
