No unhappy complex system is alike: Each is unhappy in its own way. A growing line of business in software development, observability seeks to understand how and why modern software applications and teams become unhappy in order to set them on a path toward happiness, uptime and profit.
An evolution of monitoring software — which became popular during the rise of Web 2.0 applications and spawned companies such as Splunk, Datadog, New Relic and SolarWinds — observability takes the idea of simply watching IT systems a step further. While it's helpful to have dashboards that let administrators determine the health and performance of their applications at a glance, observability advocates believe what modern businesses really need are tools that help them understand the root cause of software issues.
"To help me build better software, you can't just do everything reactively anymore," Bill Staples, president of New Relic, told Protocol. "If you work reactively in today's cloud environment, you're firefighting constantly."
The idea is that it's better for software developers to understand exactly which part of their code is causing a problem and why than rely on alerts that flag problems but require painstaking analysis to identify the cause. The time that can save is important: Forward-thinking software organizations move very quickly these days, preferring to deploy small changes to their code on a frequent basis rather than deploying big changes at a slower pace.
"If it takes you two months to ship your code, you're probably not high enough to ride this ride," said Charity Majors, co-founder and CTO of Honeycomb, one of several startups pushing the boundaries of this emerging field.
But it's not just coding: Observability tools can also help companies understand how their people are performing, and how the structure of their organization might be causing more problems than it is solving.
"The tech metrics don't mean anything without understanding the pressures that people are under when they are building the systems," said Nora Jones, co-founder and CEO of startup Jeli.
Watching, waiting, commiserating
Administrators have been monitoring the performance of computers since the first was plugged into a wall. But the modern concept of application performance management started to come together alongside the wave of enterprise software innovation that came out of the Great Recession.
As new SaaS tools started to become some of the most important operational tools inside businesses, performance — always important — took on new meaning. Customers increasingly had expectations for how software delivered over the web should perform, and as lots of these application vendors built their services atop metered cloud computing platforms from AWS and others, they had to be very aware of how much computing resource they were consuming on the back end.
The growing consensus around the value of frequent deployment meant that software developers needed tools to quickly measure the impact of those changes so they could pull back a change that introduces a new problem, said John Allspaw, co-founder of Adaptive Capacity Labs, who played key roles at Yahoo's Flickr and later Etsy during the period in which monitoring became table stakes.
"There was a period of time where some companies totally got [the idea of frequent deployment], and can't imagine working a different way and other companies can't even imagine why you would even try to deploy more than once a day," he said. That latter group gets the benefits of continuous deployment now, he said, which has lifted the fortunes of companies like JFrog, CircleCI and CloudBees, which have all built businesses around making software pipelines more efficient..
But early monitoring tools that were used to study software once it was deployed were passive, and didn't provide as complete a picture of how an application was performing.
"Maybe 10 years ago, the way things would work is developers would write the application and then hand it off to an IT pro, who would probably deploy it onto a server in a data center," Staples said. "Meanwhile, they hope that the system keeps up and running and the IT pro will tell them if something breaks — otherwise, they just go on to the next feature."
A decade later, that approach will not fly. Companies no longer separate software development from operations: a shift known as DevOps, which calls for closer cooperation between the teams and forces developers to be more aware of the impact of their changes.
One of the big risks of making changes to a monolithic application was the chance that you could cause a difficult-to-detect problem in a completely unrelated part of the app. Microservices changed that, allowing developers to break their applications down into lots of smaller pieces that can be operated and tweaked separately. At the same time, cloud adoptees started moving toward deploying their applications in containers, which meant they could be deployed across a wide range of servers.
Something more sophisticated was required to understand how all of that was working.
Disturbance in the system
"Observability is all about looking at [the application]; shipping the code and looking through instrumentation to know if it is doing what I expected it to do," Majors said.
Honeycomb's approach was modeled after the notion of control theory in mechanical engineering, she said. Its tools give operations engineers a way to build instrumentation into their code to flag problems as they happen, allowing them to discover exactly where something has gone wrong rather than seeing a poor end-user performance and digging through the code to find the problem.
Usually software organizations aren't dealing with issues like the massive outage that took down Slack last week: Most software incidents are minor, Staples said.
"When things fail, they don't fail completely. You see drop-off rates, you see errors fail for 10 percent of users," he said. "What you do as an engineer is you're constantly using those signals: to know where to go invest more, whether it's improving the feature to get the customer through a trouble spot that's slowing them down and keeping them on, whether it's scaling a part of the system to increase the performance of that component or other things."
Fixing those problems quickly, rather than spending time debugging a poorly-performing application, can give software teams more time to focus on improving their products.
"Code is like food; it rots," Majors said. Preventing that rot from dragging down an entire system as quickly as possible can prevent bigger outages down the road that cost companies money.
But it's not just the code that needs observing; it's the people.
Jones is a veteran of high-performing software teams at Slack, Netflix and Jet.com. Yet even within companies at the forefront of software development practices, organizational structures can make as much of an impact on healthy applications as coding practices, she said.
At one of those companies (she declined to share which), a disproportionately large number of performance issues happened within a short period of time each year, and the company was having a hard time figuring out what was causing the problem. Turns out, those problematic periods came just after its annual promotions cycle, during which engineers had scrambled to ship as much code as they could in a short period of time to hit their goals for the year.
"It wasn't their fault. It was the system that was created at the company," Jones said. "Understanding that these promotion cycles were being correlated to an increase in incidents, because people were trying to get things done really quickly, actually incentivized the company to completely restructure how they did their promotion cycles, which led to this kind of stuff not happening as much."
Insights like that led Jones to found Jeli, which allows companies to evaluate and monitor how their organizational structures map against their coding practices. The company just raised a $4 million seed round to build out tools for that type of customer.
The promise of observability tools is preventative maintenance: Not only will you be able to see and react to problems faster than current monitoring tools allow, but you'll also be able to glean insights from that data in a way that helps protect against future problems yet to rear their head.
The surge of interest in this space from upstarts and traditional monitoring companies has lots of ideas flying fast and furious, but it will take some time before that promise will be met, according to Allspaw.
"We have enough problems with the known unknowns," he said. "The runway to make progress on that is as close to infinite as we can get."
Still, 25 years into the internet revolution, we've come to expect certain levels of performance and reliability from our web and mobile applications. Big organizations like AWS, Google, Netflix and others are well down the observability road inside their own companies. And now the tools and companies that will bring those insights to the rest of us are starting to get traction.