"Like many organizations, we considered Istio. But our research led to the conclusion that we would need a team of developers just to run it. It was too complicated, requiring ongoing, active attention—it’s not fire and forget. We looked at other solutions and ended up with a shortlist of half a dozen different options, but the one that stood out was Linkerd."
"We installed Linkerd and everything was just working right — we didn’t have to add any extra configurations or anything like that. With Istio, we would have had to make a bunch of changes to make everything work."
"We’ve felt encumbered by [Istio’s] complexity every time when configuring, maintaining or troubleshooting in our clusters. After yet another ‘Oh… This problem was caused by Istio!’-moment, we decided the time was ripe to consider the alternatives. We looked to the grand ol’ Internet for alternatives and fixed our gaze on the rising star Linkerd."
The service mesh is here to stay, and Kubernetes adopters around the world are
deciding between Istio and Linkerd. In 2022, engineers are increasingly
choosing Linkerd. Why is that?
In this comparison, we’ll walk you through the similarities and differences
between the projects and when to choose one over the other.
The big picture
Istio and Linkerd are both service meshes. The two
projects have similar goals: to add reliability, security, and observability to
Kubernetes applications. Both proejcts work by adding transparent “sidecar
proxies” alongside application instances, and providing features by through
Despite these similarities, the two projects couldn’t be more different. Istio
is a “big vendor” project, with the complexity to match. Linkerd takes the
opposite approach, focusing on simplicity (especially operational simplicity),
performance, and user experience.
We’re biased, of course, but here’s our take on the comparison—including
situations where you should choose Istio over Linkerd!
Why choose Linkerd over Istio?
In short, you should choose Linkerd if you are focused on Kubernetes and
want a service mesh that gets out of your way. Unless you have a complex set of
requirements that Linkerd simply can’t address, Linkerd will make your life
Linkerd is faster
Linkerd is significantly faster than Istio, meaning that your users and
customers will experience better performance. In the project’s recent service
Linkerd added anywhere from 40% to 400% less latency than Istio did. Why is
this? Linkerd’s state-of-the-art, ultralight Rust “micro-proxy” is designed
just for the service mesh use case and can be highly optimized to handle this
Linkerd consumed significantly fewer system resources than Istio, especially at
the critical data plane level (which scales with your application). In the
project’s recent service mesh
Linkerd used an order of magnitude less CPU and memory than Istio. The
primary reason? Again, Linkerd’s ultralight Rust “micro-proxy”, designed
specifically for the service mesh usecase.
Linkerd makes it easier to build secure systems. Linkerd’s configuration
surface area is significantly smaller than that of Istio, and security features
like mutual TLS are on by default. (In other words, the moment you install
Linkerd, all communication between meshed pods is automatically encrypted and
validated with mutual TLS, no configuration required!)
Istio uses the general-purpose Envoy proxy, which is built on C++, a legacy
language known for its memory-related security vulnerabilities. By contrast,
Linkerd’s data plane is built in Rust, a language that avoids the entire class
of memory-related CVEs through advanced memory management. The Linkerd
team believes that the future of the cloud will be built in
"One astonishing fact sticks out: the majority of vulnerabilities fixed and with a CVE assigned are caused by developers inadvertently inserting memory corruption bugs into their C and C++ code. — Microsoft,"
Linkerd’s core design philosophy is about minimalism: a service mesh should be
simple, light, and secure, and do as little as possible to get the job done.
Linkerd is especially focused on reducing operational complexity: the human
toil involved in maintaining, operating, and being on-call for a production
Istio takes a different approach and presents an all-in-one solution. Many
features and configurations are supported, from built-in ingress controllers to
multiple types of multi-cluster operations. This allows Istio to tackle a range
of complex situations, but also means that Istio is extremely difficult to
operate and configure.
Linkerd is a graduated project of the Cloud Native Computing
Foundation, the same neutral foundation that hosts
Kubernetes, Prometheus, and other core cloud native projects. Linkerd has
publicly committed to open
has over 200+ contributors from all over the world, and a public steering
committee of end users. Istio, by contrast, is not a CNCF project but is hosted
in the OUC, a foundation that Google created specifically for it.
Linkerd users get free access to Buoyant Cloud, a hosted dashboard
that allows you to share your Linkerd metrics and mesh health with your team.
You can get support directly from the Linkerd maintainers
While Istio support requires going to a third-party vendor, you can get Linkerd
support from the creators and maintainers themselves. Linkerd help is available
around the clock in a variety of levels, from erd’s thriving and friendly open
source community all the way to 24x7x365 Linkerd support from the creators of
Why choose Istio over Linkerd?
There are some perfectly valid reasons why you might choose Istio over Linkerd.
For one, Linkerd is very Kuberenetes-focused, and organizations that are not
ready to adopt the Kubernetes operational model as their primary model may find
Istio better suited to their needs. Istio is also extremely configurable, and
users that have very specialized requirements may only be able to satisfy those
requirements with Istio.
Of course, choosing Istio only makes sense if you have the engineering resources
to dedicate to it. Istio adopters often resort to handling its complexity by
hiring a team of service mesh engineers.
The bottom line
If security is a primary concern; if you want a service mesh that “just works”
and gets out of your way; if speed and resource consumption are critical; and
if you are bought into the Kubernetes model of operations—Linkerd will be the
best choice. If you have highly specialized requirements that Linkerd can’t
meet, and are willing to make the requisite engineering investment in Istio,
then you should use Istio.