Alex Krivit
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Alex Krivit
Introducing Speed Brain: helping web pages load 45% faster
Each time a user visits your web page, they are initiating a race to receive content as quickly as possible. Performance is a critical factor that influences how visitors interact with your site. Some might think that moving content across the globe introduces significant latency, but for a while, network transmission speeds have approached their theoretical limits. To put this into perspective, data on Cloudflare can traverse the 11,000 kilometer round trip between New York and London in about 76 milliseconds – faster than the blink of an eye.
However, delays in loading web pages persist due to the complexities of processing requests, responses, and configurations. In addition to pushing advancements in connection establishment, compression, hardware, and software, we have built a new way to reduce page load latency by anticipating how visitors will interact with a given web page.
Today we are very excited to share the latest leap forward in speed: Speed Brain. It relies on the Speculation Rules API to prefetch the content of the user's likely next navigations. The main goal of Speed Brain is to download a web page to the browser cache before a user navigates to it, allowing Continue reading
Instant Purge: invalidating cached content in under 150ms
(part 3 of the Coreless Purge series)
Over the past 14 years, Cloudflare has evolved far beyond a Content Delivery Network (CDN), expanding its offerings to include a comprehensive Zero Trust security portfolio, network security & performance services, application security & performance optimizations, and a powerful developer platform. But customers also continue to rely on Cloudflare for caching and delivering static website content. CDNs are often judged on their ability to return content to visitors as quickly as possible. However, the speed at which content is removed from a CDN's global cache is just as crucial.
When customers frequently update content such as news, scores, or other data, it is essential they avoid serving stale, out-of-date information from cache to visitors. This can lead to a subpar experience where users might see invalid prices, or incorrect news. The goal is to remove the stale content and cache the new version of the file on the CDN, as quickly as possible. And that starts by issuing a “purge.”
In May 2022, we released the first part of the series detailing our efforts to rebuild and publicly document the steps taken to improve the system our customers use, Continue reading
Introducing Automatic SSL/TLS: securing and simplifying origin connectivity
During Birthday Week 2022, we pledged to provide our customers with the most secure connection possible from Cloudflare to their origin servers automatically. I’m thrilled to announce we will begin rolling this experience out to customers who have the SSL/TLS Recommender enabled on August 8, 2024. Following this, remaining Free and Pro customers can use this feature beginning September 16, 2024 with Business and Enterprise customers to follow.
Although it took longer than anticipated to roll out, our priority was to achieve an automatic configuration both transparently and without risking any site downtime. Taking this additional time allowed us to balance enhanced security with seamless site functionality, especially since origin server security configuration and capabilities are beyond Cloudflare's direct control. The new Automatic SSL/TLS setting will maximize and simplify the encryption modes Cloudflare uses to communicate with origin servers by using the SSL/TLS Recommender.
We first talked about this process in 2014: at that time, securing connections was hard to configure, prohibitively expensive, and required specialized knowledge to set up correctly. To help alleviate these pains, Cloudflare introduced Universal SSL, which allowed web properties to obtain a free SSL/TLS certificate to enhance the security of connections between browsers Continue reading
Introducing Automatic SSL/TLS: securing and simplifying origin connectivity
During Birthday Week 2022, we pledged to provide our customers with the most secure connection possible from Cloudflare to their origin servers automatically. I’m thrilled to announce we will begin rolling this experience out to customers who have the SSL/TLS Recommender enabled on August 8, 2024. Following this, remaining Free and Pro customers can use this feature beginning September 16, 2024, with Business and Enterprise customers to follow.
Although it took longer than anticipated to roll out, our priority was to achieve an automatic configuration both transparently and without risking any site downtime. Taking this additional time allowed us to balance enhanced security with seamless site functionality, especially since origin server security configuration and capabilities are beyond Cloudflare's direct control. The new Automatic SSL/TLS setting will maximize and simplify the encryption modes Cloudflare uses to communicate with origin servers by using the SSL/TLS Recommender.
We first talked about this process in 2014: at that time, securing connections was hard to configure, prohibitively expensive, and required specialized knowledge to set up correctly. To help alleviate these pains, Cloudflare introduced Universal SSL, which allowed web properties to obtain a free SSL/TLS certificate to enhance the security of connections between browsers and Continue reading
Cache Reserve goes GA: enhanced control to minimize egress costs
Everyone is chasing the highest cache ratio possible. Serving more content from Cloudflare’s cache means it loads faster for visitors, saves website operators money on egress fees from origins, and provides multiple layers of resiliency and protection to make sure that content is available to be served and websites scale effortlessly. A year ago we introduced Cache Reserve to help customer’s serve as much content as possible from Cloudflare’s cache.
Today, we are thrilled to announce the graduation of Cache Reserve from beta to General Availability (GA), accompanied by the introduction of several exciting new features. These new features include adding Cache Reserve into the analytics shown on the Cache overview section of the Cloudflare dashboard, giving customers the ability to see how they are using Cache Reserve over time. We have also added the ability for customers to delete all data in Cache Reserve without losing content in the edge cache. This is useful for customers who are no longer using Cache Reserve storage.
We’re also introducing new tools that give organizations more granular control over which files are saved to Cache Reserve, based on valuable feedback we received during the beta. The default configuration of Cache Reserve Continue reading
Cache Rules go GA: precision control over every part of your cache
One year ago we introduced Cache Rules, a new way to customize cache settings on Cloudflare. Cache Rules provide greater flexibility for how users cache content, offering precise controls, a user-friendly API, and seamless Terraform integrations. Since it was released in late September 2022, over 100,000 websites have used Cache Rules to fine-tune their cache settings.
Today, we're thrilled to announce that Cache Rules, along with several other Rules products, are generally available (GA). But that’s not all — we're also introducing new configuration options for Cache Rules that provide even more options to customize how you cache on Cloudflare. These include functionality to define what resources are eligible for Cache Reserve, what timeout values should be respected when receiving data from your origin server, which custom ports we should use when we cache content, and whether we should bypass Cloudflare’s cache in the absence of a cache-control header.
Cache Rules give users full control and the ability to tailor their content delivery strategy for almost any use case, without needing to write code. As Cache Rules go GA, we are incredibly excited to see how fast customers can achieve their perfect cache strategy.
History of Customizing Cache Continue reading
Speeding up your (WordPress) website is a few clicks away
Every day, website visitors spend far too much time waiting for websites to load in their browsers. This waiting is partially due to browsers not knowing which resources are critically important so they can prioritize them ahead of less-critical resources. In this blog we will outline how millions of websites across the Internet can improve their performance by specifying which critical content loads first with Cloudflare Workers and what Cloudflare will do to make this easier by default in the future.
Popular Content Management Systems (CMS) like WordPress have made attempts to influence website resource priority, for example through techniques like lazy loading images. When done correctly, the results are magical. Performance is optimized between the CMS and browser without needing to implement any changes or coding new prioritization strategies. However, we’ve seen that these default priorities have opportunities to improve greatly.
In this co-authored blog with Google’s Patrick Meenan we will explain where the opportunities exist to improve website performance, how to check if a specific site can improve performance, and provide a small JavaScript snippet which can be used with Cloudflare Workers to do this optimization for you.
What happens when a browser receives the response?
Before we Continue reading
Smart Hints make code-free performance simple
This post is also available in 简体中文, 日本語, Deutsch, Français and Español.
Today, we’re excited to announce how we’re making Early Hints and Fetch Priorities automatic using the power of Cloudflare’s network. Almost a year ago we launched Early Hints. Early Hints are a method that allows web servers to asynchronously send instructions to the browser whilst the web server is getting the full response ready. This gives proactive suggestions to the browser on how to load the webpage faster for the visitor rather than idly waiting to receive the full webpage response.
In initial lab experiments, we observed page load improvements exceeding 30%. Since then, we have sent about two-trillion hints on behalf of over 150,000 websites using the product.
In order to effectively use Early Hints on a website, HTTP link headers or HTML link elements must be configured to specify which assets should be preloaded or which third-party servers should be preconnected. Making these decisions requires understanding how your website interacts with browsers, and identifying render-blocking assets to hint on without implementing prioritization strategies that saturate network bandwidth on non-critical assets (i.e. you can’t just Early Hint everything and expect good results).
For Continue reading
Reduce latency and increase cache hits with Regional Tiered Cache
Today we’re excited to announce an update to our Tiered Cache offering: Regional Tiered Cache.
Tiered Cache allows customers to organize Cloudflare data centers into tiers so that only some “upper-tier” data centers can request content from an origin server, and then send content to “lower-tiers” closer to visitors. Tiered Cache helps content load faster for visitors, makes it cheaper to serve, and reduces origin resource consumption.
Regional Tiered Cache provides an additional layer of caching for Enterprise customers who have a global traffic footprint and want to serve content faster by avoiding network latency when there is a cache miss in a lower-tier, resulting in an upper-tier fetch in a data center located far away. In our trials, customers who have enabled Regional Tiered Cache have seen a 50-100ms improvement in tail cache hit response times from Cloudflare’s CDN.
What problem does Tiered Cache help solve?
First, a quick refresher on caching: a request for content is initiated from a visitor on their phone or computer. This request is generally routed to the closest Cloudflare data center. When the request arrives, we look to see if we have the content cached to respond to Continue reading
Reduce origin load, save on cloud egress fees, and maximize cache hits with Cache Reserve
Earlier this year, we introduced Cache Reserve. Cache Reserve helps users serve content from Cloudflare’s cache for longer by using R2’s persistent data storage. Serving content from Cloudflare’s cache benefits website operators by reducing their bills for egress fees from origins, while also benefiting website visitors by having content load faster.
Cache Reserve has been in closed beta for a few months while we’ve collected feedback from our initial users and continued to develop the product. After several rounds of iterating on this feedback, today we’re extremely excited to announce that Cache Reserve is graduating to open beta – users will now be able to test it and integrate it into their content delivery strategy without any additional waiting.
If you want to see the benefits of Cache Reserve for yourself and give us some feedback– you can go to the Cloudflare dashboard, navigate to the Caching section and enable Cache Reserve by pushing one button.
How does Cache Reserve fit into the larger picture?
Content served from Cloudflare’s cache begins its journey at an origin server, where the content is hosted. When a request reaches the origin, the origin compiles the content needed for the response and sends Continue reading
Automatic (secure) transmission: taking the pain out of origin connection security
In 2014, Cloudflare set out to encrypt the Internet by introducing Universal SSL. It made getting an SSL/TLS certificate free and easy at a time when doing so was neither free, nor easy. Overnight millions of websites had a secure connection between the user’s browser and Cloudflare.
But getting the connection encrypted from Cloudflare to the customer’s origin server was more complex. Since Cloudflare and all browsers supported SSL/TLS, the connection between the browser and Cloudflare could be instantly secured. But back in 2014 configuring an origin server with an SSL/TLS certificate was complex, expensive, and sometimes not even possible.
And so we relied on users to configure the best security level for their origin server. Later we added a service that detects and recommends the highest level of security for the connection between Cloudflare and the origin server. We also introduced free origin server certificates for customers who didn’t want to get a certificate elsewhere.
Today, we’re going even further. Cloudflare will shortly find the most secure connection possible to our customers’ origin servers and use it, automatically. Doing this correctly, at scale, while not breaking a customer’s service is very complicated. This blog post explains how we are Continue reading
Introducing Cache Rules: precision caching at your fingertips
Ten years ago, in 2012, we released a product that put “a powerful new set of tools” in the hands of Cloudflare customers, allowing website owners to control how Cloudflare would cache, apply security controls, manipulate headers, implement redirects, and more on any page of their website. This product is called Page Rules and since its introduction, it has grown substantially in terms of popularity and functionality.
Page Rules are a common choice for customers that want to have fine-grained control over how Cloudflare should cache their content. There are more than 3.5 million caching Page Rules currently deployed that help websites customize their content. We have spent the last ten years learning how customers use those rules to cache content, and it’s clear the time is ripe for evolving rules-based caching on Cloudflare. This evolution will allow for greater flexibility in caching different types of content through additional rule configurability, while providing more visibility into when and how different rules interact across Cloudflare’s ecosystem.
Today, we’ve announced that Page Rules will be re-imagined into four product-specific rule sets: Origin Rules, Cache Rules, Configuration Rules, and Redirect Rules.
In this blog we’re going to discuss Cache Rules, and Continue reading
Crawler Hints supports Microsoft’s IndexNow in helping users find new content
The web is constantly changing. Whether it’s news or updates to your social feed, it’s a constant flow of information. As a user, that’s great. But have you ever stopped to think how search engines deal with all the change?
It turns out, they “index” the web on a regular basis — sending bots out, to constantly crawl webpages, looking for changes. Today, bot traffic accounts for about 30% of total traffic on the Internet, and given how foundational search is to using the Internet, it should come as no surprise that search engine bots make up a large proportion of that what might come as a surprise is how inefficient the model is, though: we estimate that over 50% of crawler traffic is wasted effort.
This has a huge impact. There’s all the additional capacity that owners of websites need to bake into their site to absorb the bots crawling all over it. There’s the transmission of the data. There’s the CPU cost of running the bots. And when you’re running at the scale of the Internet, all of this has a pretty big environmental footprint.
Part of the problem, though, is nobody had really stopped to ask: maybe Continue reading
Early Hints update: How Cloudflare, Google, and Shopify are working together to build a faster Internet for everyone
A few months ago, we wrote a post focused on a product we were building that could vastly improve page load performance. That product, known as Early Hints, has seen wide adoption since that original post. In early benchmarking experiments with Early Hints, we saw performance improvements that were as high as 30%.
Now, with over 100,000 customers using Early Hints on Cloudflare, we are excited to talk about how much Early Hints have improved page loads for our customers in production, how customers can get the most out of Early Hints, and provide an update on the next iteration of Early Hints we’re building.
What Are Early Hints again?
As a reminder, the browser you’re using right now to read this page needed instructions for what to render and what resources (like images, fonts, and scripts) need to be fetched from somewhere else in order to complete the loading of this (or any given) web page. When you decide you want to see a page, your browser sends a request to a server and the instructions for what to load come from the server’s response. These responses are generally composed of a multitude of resources that tell the browser Continue reading
Part 1: Rethinking Cache Purge, Fast and Scalable Global Cache Invalidation
There is a famous quote attributed to a Netscape engineer: “There are only two difficult problems in computer science: cache invalidation and naming things.” While naming things does oddly take up an inordinate amount of time, cache invalidation shouldn’t.
In the past we’ve written about Cloudflare’s incredibly fast response times, whether content is cached on our global network or not. If content is cached, it can be served from a Cloudflare cache server, which are distributed across the globe and are generally a lot closer in physical proximity to the visitor. This saves the visitor’s request from needing to go all the way back to an origin server for a response. But what happens when a webmaster updates something on their origin and would like these caches to be updated as well? This is where cache “purging” (also known as “invalidation”) comes in.
Customers thinking about setting up a CDN and caching infrastructure consider questions like:
- How do different caching invalidation/purge mechanisms compare?
- How many times a day/hour/minute do I expect to purge content?
- How quickly can the cache be purged when needed?
This blog will discuss why invalidating cached assets is hard, what Cloudflare has done to make Continue reading
Introducing Cache Reserve: massively extending Cloudflare’s cache
One hundred percent. 100%. One-zero-zero. That’s the cache ratio we’re all chasing. Having a high cache ratio means that more of a website’s content is served from a Cloudflare data center close to where a visitor is requesting the website. Serving content from Cloudflare’s cache means it loads faster for visitors, saves website operators money on egress fees from origins, and provides multiple layers of resiliency and protection to make sure that content is reliably available to be served.
Today, I’m delighted to announce a massive extension of the benefits of caching with Cache Reserve: a new way to persistently serve all static content from Cloudflare’s global cache. By using Cache Reserve, customers can see higher cache hit ratios and lower egress bills.
Why is getting a 100% cache ratio difficult?
Every second, Cloudflare serves tens-of-millions of requests from our cache which equates to multiple terabytes-per-second of cached data being delivered to website visitors around the world. With this massive scale, we must ensure that the most requested content is cached in the areas where it is most popular. Otherwise, visitors might wait too long for content to be delivered from farther away and our network would be running inefficiently. Continue reading
Crawler Hints Update: Cloudflare Supports IndexNow and Announces General Availability
In the midst of the hottest summer on record, Cloudflare held its first ever Impact Week. We announced a variety of products and initiatives that aim to make the Internet and our planet a better place, with a focus on environmental, social, and governance projects. Today, we’re excited to share an update on Crawler Hints, an initiative announced during Impact Week. Crawler Hints is a service that improves the operating efficiency of the approximately 45% of Internet traffic that comes from web crawlers and bots.
Crawler Hints achieves this efficiency improvement by ensuring that crawlers get information about what they’ve crawled previously and if it makes sense to crawl a website again.
Today we are excited to announce two updates for Crawler Hints:
- The first: Crawler Hints now supports IndexNow, a new protocol that allows websites to notify search engines whenever content on their website content is created, updated, or deleted. By collaborating with Microsoft and Yandex, Cloudflare can help improve the efficiency of their search engine infrastructure, customer origin servers, and the Internet at large.
- The second: Crawler Hints is now generally available to all Cloudflare customers for free. Customers can benefit from these more Continue reading
Early Hints: How Cloudflare Can Improve Website Load Times by 30%
Want to know a secret about Internet performance? Browsers spend an inordinate amount of time twiddling their thumbs waiting to be told what to do. This waiting impacts page load performance. Today, we’re excited to announce support for Early Hints, which dramatically improves browser page load performance and reduces thumb-twiddling time.
In initial tests using Early Hints, we have observed more than 30% improvement to page load time for browsers visiting a website for the first time.
Early Hints is available in beta today — Cloudflare customers can request access to Early Hints in the dashboard’s Speed tab. It’s free for all customers because we think the web should be fast!
Early Hints in a nutshell
Browsers need instructions for what to render and what resources need to be fetched to complete “painting” a given web page. These instructions come from a server response. But the servers sending these responses often need time to compile these resources — this is known as “server think time.” While the servers are busy during this time… browsers sit idle and wait.
Early Hints takes advantage of “server think time” to asynchronously send instructions to the browser to begin loading resources while the Continue reading
Introducing Smart Edge Revalidation
Today we’re excited to announce Smart Edge Revalidation. It was designed to ensure that compute resources are synchronized efficiently between our edge and a browser. Right now, as many as 30% of objects cached on Cloudflare’s edge do not have the HTTP response headers required for revalidation. This can result in unnecessary origin calls. Smart Edge Revalidation fixes this: it does the work to ensure that these headers are present, even when an origin doesn’t send them to us. The advantage of this? There’s less wasted bandwidth and compute for objects that do not need to be redownloaded. And there are faster browser page loads for users.
So What Is Revalidation?
Revalidation is one part of a longer story about efficiently serving objects that live on an origin server from an intermediary cache. Visitors to a website want it to be fast. One foundational way to make sure that a website is fast for visitors is to serve objects from cache. In this way, requests and responses do not need to transit unnecessary parts of the Internet back to an origin and, instead, can be served from a data center that is closer to the visitor. As such, website operators Continue reading
CDN-Cache-Control: Precision Control for your CDN(s)
Today we are thrilled to announce our support of a new set of HTTP response headers that provide surgical control over our CDN’s caching decisions. CDN-Cache-Control allows customers to directly control how our CDN behaves without affecting the behavior of downstream or upstream caches.
You might be thinking that this sounds a lot like the Cache-Control header we all know and love. And it’s very similar! CDN-Cache-Control has exactly the same directives as the Cache-Control header. The problem CDN-Cache-Control sets out to solve is that with Cache-Control, some directives are targeted at specific classes of caches (like s-maxage for shared caches), while other directives are not targeted at controlling any specific classes of intermediary caches (think stale-while-revalidate). As these non-specific directives are returned to downstream caches, they’re often not applied uniformly. This problem is amplified as the number of intermediary caches grows between an origin and the client.
For example, a website may deploy a caching layer on the origin server itself, there might be a cache on the origin’s network, the site might use one or more CDNs to cache content distributed throughout the Internet, and the visitor’s browser might cache content as well. As the response returns Continue reading