This put up is cowritten with Nikos Tragaras and Raphaël Afanyan from Nexthink.
On this put up, we describe Nexthink’s journey as they applied a brand new real-time alerting system utilizing Amazon Managed Service for Apache Flink. We discover the structure, the rationale behind key expertise selections, and the Amazon Internet Companies (AWS) companies that enabled a scalable and environment friendly answer.
Nexthink is a pioneering chief in digital worker expertise (DEX). With a mission to empower IT groups and elevate office productiveness, Nexthink’s Infinity platform gives real-time visibility into finish consumer environments, actionable insights, and sturdy automation capabilities. By combining real-time analytics, proactive monitoring, and clever automation, Infinity permits organizations to ship an optimum digital workspace.
Previously 5 years, Nexthink accomplished its transformation right into a fully-fledged cloud platform that processes trillions of occasions per day, reaching over 5 GB per second of aggregated throughput. Internally, Infinity includes greater than 300 microservices that use the ability of Apache Kafka by Amazon Managed Service for Apache Kafka (Amazon MSK) for information ingestion and intra-service communication. The Nexthink ecosystem contains a number of a whole bunch of Micronaut-based Java microservices deployed in Amazon Elastic Kubernetes Service (Amazon EKS). The overwhelming majority of microservices work together with Kafka by the Kafka Streams framework.
Nexthink alerting system
That will help you perceive Nexthink’s journey towards a brand new real-time alerting answer, we start by inspecting the prevailing system and the evolving necessities that led them to hunt a brand new answer.
Nexthink’s present alerting system supplies close to real-time notifications, serving to customers detect and reply to important occasions rapidly. Whereas efficient, this technique has limitations in scalability, flexibility, and real-time processing capabilities.
Nexthink gathers telemetry information from hundreds of shoppers’ laptops protecting CPU utilization, reminiscence, software program variations, community efficiency, and extra. Amazon MSK and ClickHouse function the spine for this information pipeline. All endpoint information is ingested in Kafka multi-tenant matters, that are processed and at last saved in a ClickHouse database.
Utilizing the present alerting system, shoppers can outline monitoring guidelines in Nexthink Question Language (NQL), that are evaluated in close to actual time by polling the database each quarter-hour. Alerts are triggered when anomalies are detected towards client-defined thresholds or long-term baselines. This course of is illustrated within the following structure diagram.
Initially, database-polling allowed nice flexibility within the analysis of advanced alerts. Nevertheless, this strategy positioned heavy stress on the database. As the corporate grew and supported bigger clients with extra endpoints and displays, the database skilled more and more heavy masses.
Evolution to a brand new use-case: Actual-time alerts
As Nexthink expanded its information assortment to incorporate digital desktop infrastructure (VDI), the necessity for real-time alerting turned much more important. Not like conventional endpoints, equivalent to laptops, the place occasions are gathered each 5 minutes, VDI information is ingested each 30 seconds—considerably rising the amount and frequency of information. The present structure relied on database polling to guage alerts, operating at a 15-minute interval. This strategy was insufficient for the brand new VDI use case, the place alerts wanted to be evaluated in close to actual time on messages arriving each 30 seconds. Merely rising the polling frequency wasn’t a viable possibility as a result of it could place extreme load on the database, resulting in efficiency bottlenecks and scalability challenges. To satisfy these new calls for effectively, we shifted to real-time alert analysis instantly on Kafka matters.
Expertise choices
As we evaluated options for our real-time alerting system, we analyzed two major expertise choices: Apache Kafka Streams and Apache Flink. Every possibility had advantages and limitations that wanted to be thought of.
All Nexthink microservices as much as that time built-in with Kafka utilizing Apache Kafka Streams. We’ve noticed in observe a number of advantages:
- Light-weight and seamless integration. No want for extra infrastructure.
- Low latency utilizing RocksDB as an area key-value retailer.
- Group experience. Nexthink groups have been writing microservices with Kafka-streams for a very long time and really feel very snug utilizing it.
In some use instances nevertheless, we discovered that there have been essential limitations:
- Scalability – Scalability was constrained by the tight coupling between parallelism of microservices and the variety of partitions in Kafka matters. Many microservices had already scaled out to match the partition depend of the matters they consumed, limiting their capacity to scale additional. One potential answer was rising the partition depend. Nevertheless, this strategy launched important operational overhead, particularly with microservices consuming matters owned by different domains. It required rebalancing all the Kafka cluster and wanted coordination throughout a number of groups. Moreover, such modifications impacted downstream companies, requiring cautious reconfiguration of stateful processing. The choice strategy can be to introduce intermediate matters to redistribute workload, however this may add complexity to the information pipeline and improve useful resource consumption on Kafka. These challenges made it clear {that a} extra versatile and scalable strategy was wanted.
- State administration – Companies that wanted to create massive Ok-tables in reminiscence had an elevated startup time. Additionally, in instances the place the interior state was massive in quantity, we discovered that it utilized important load to the Kafka cluster through the creation of the interior state.
- Late occasion processing – In windowing operations, late occasions needed to be managed manually with methods that complexified the codebase.
Looking for an alternate that might assist us overcome the challenges posed by our present system, we determined to guage Flink. Its sturdy streaming capabilities, scalability, and adaptability made it a wonderful alternative for constructing real-time alerting methods based mostly on Kafka matters. A number of benefits made Flink significantly interesting:
- Native integration with Kafka – Flink gives native connectors for Kafka, which is a central element within the Nexthink ecosystem.
- Occasion-time processing and assist for late occasions – Flink permits messages to be processed based mostly on the occasion time (that’s, when the occasion really occurred) even when they arrive out of order. This function is essential for real-time alerts as a result of it ensures their accuracy.
- Scalability – Flink’s distributed structure permits it to scale horizontally independently from the variety of partitions within the Kafka matters. This function weighed rather a lot in our decision-making as a result of the dependence on the variety of partitions was a powerful limitation in our platform up so far.
- Fault tolerance – Flink helps checkpoints, permitting managed state to be continued and guaranteeing constant restoration in case of failures. Not like Kafka Streams, which depends on Kafka itself for long-term state persistence (including further load to the cluster), Flink’s checkpointing mechanism operates independently and runs out-of-band, minimizing the affect on Kafka whereas offering environment friendly state administration.
- Amazon Managed Service for Apache Flink – Amazon Managed Service for Apache Flink is a totally managed service that simplifies the deployment, scaling, and administration of Flink purposes for real-time information processing. By eliminating the operational complexities of managing Flink clusters, AWS permits organizations to give attention to constructing and operating real-time analytics and event-driven purposes effectively. Amazon Managed Service for Apache Flink offered us with important flexibility. It streamlined our analysis course of, which meant we may rapidly arrange a proof-of-concept setting with out entering into the complexities of managing an inside Flink cluster. Furthermore, by decreasing the overhead of cluster administration, it made Flink a viable expertise alternative and accelerated our supply timeline.
Answer
After cautious analysis of each choices, we selected Apache Flink as our answer on account of its superior scalability, sturdy event-time processing, and environment friendly state administration capabilities. Right here’s how we applied our new real-time alerting system.
The next diagram is the answer structure.

The primary use case was to detect points with VDI. Nevertheless, our intention was to construct a generic answer that may give us the choice to onboard sooner or later present use instances at present applied by polling. We wished to take care of a typical approach of configuring monitoring circumstances and permit alert analysis each with polling in addition to in actual time, relying on the kind of machine being monitored.
This answer includes a number of elements:
- Monitor configuration – Utilizing Nexthink Question Language (NQL), the alerts administrator defines a monitor that specifies, for instance:
- Information supply – VDI occasions
- Time window – Each 30 seconds
- Metric – Common community latency, grouped by desktop pool
- Set off situation(s) – Latency exceeding 300 ms for a continuous interval of 5 minutes
This monitor configuration is then saved in an internally developed doc retailer and propagated downstream in a Kafka matter.
- Information processing utilizing Generic Stream Companies– The Nexthink Collector, an agent put in on endpoints, captures and experiences numerous sorts of actions from the VDI endpoints the place it’s put in. These occasions are forwarded to Amazon MSK in considered one of Nexthink’s manufacturing digital non-public clouds (VPCs) and are consumed by Java microservices operating on Amazon EKS belonging to a number of domains inside Nexthink
One among them is Generic Stream Companies, a system that processes the collected occasions and aggregates them in buckets of 30 seconds. This element works as self-service for all of the function groups in Nexthink and may question and mixture information from an NQL question. This fashion, we had been in a position to preserve a unified consumer expertise on monitor configuration utilizing NQL, no matter how alerts had been evaluated. This element is damaged down into two companies:
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- GS processor – Consumes uncooked VDI session occasions and applies preliminary processing
- GS aggregator – Teams and aggregates the information based on the monitor configuration
- Actual-time monitoring utilizing Flink – Static threshold alerting and seasonal change detection, which identifies variations in information that comply with a recurring sample over time, are the 2 varieties of detection that we provide for VDI points. The system splits the processing between two purposes:
- Baseline utility – Calculates statistical baselines with seasonality utilizing time-of-day anomaly algorithm. For instance, the latency by VDI consumer location or the CPU queue size of a desktop pool.
- Alert utility – Generates alerts based mostly on user-defined thresholds when the sudden values don’t change over time or dynamic thresholds based mostly on baselines, which set off when a metric deviates from an anticipated sample.
The next diagram illustrates how we be part of VDI metrics with monitor configurations, mixture information utilizing sliding time home windows, and consider threshold guidelines, all inside Apache Flink. From this course of, alerts are generated and are then grouped and filtered earlier than being processed additional by the shoppers of alerts.

- Alert processing and notifications – After an alert is triggered (when a threshold is exceeded) or recovered (when a metric returns to regular ranges), the system will assess their affect to prioritize response by the affect processing module. Alerts are then consumed by notification companies that ship messages by emails or webhooks. The alert and affect information are then ingested right into a time collection database.
Advantages of the brand new structure
One of many key benefits of adopting a streaming-based strategy over polling was its ease of configuration and administration, particularly for a small group of three engineers. There was no want for cluster administration, so all we would have liked to do was to provision the service and begin coding.
Given our prior expertise with Kafka and Kafka Streams and mixed with the simplicity of a managed service, we had been in a position to rapidly develop and deploy a brand new alerting system with out the overhead of advanced infrastructure setup. We used Amazon Managed Service for Apache Flink to spin up a proof of idea inside a couple of hours, which meant the group may give attention to defining the enterprise logic with out having considerations associated to cluster administration.
Initially, we had been involved in regards to the challenges of becoming a member of a number of Kafka matters. With our earlier Kafka Streams implementation, joined matters required equivalent partition keys, a constraint referred to as co-partitioning. This created an rigid structure, significantly when integrating matters throughout completely different enterprise domains. Every area naturally had its personal optimum partitioning technique, forcing tough compromises.
Amazon Managed Service for Apache Flink solved this downside by its inside information partitioning capabilities. Though Flink nonetheless incurs some community site visitors when redistributing information throughout the cluster throughout joins, the overhead is virtually negligible. The ensuing structure is each extra scalable (as a result of matters could be scaled independently based mostly on their particular throughput necessities) and simpler to take care of with out advanced partition alignment considerations.
This considerably improved our capacity to detect and reply to VDI efficiency degradations in actual time whereas retaining our structure clear and environment friendly.
Classes learnt
As with all new expertise, adopting Flink for real-time processing got here with its personal set of challenges and insights.
One of many major difficulties we encountered was observing Flink’s inside state. Not like Kafka Streams, the place the interior state is by default backed by a Kafka matter from which its content material could be visualized, Flink’s structure makes it inherently tough to examine what is occurring inside a operating job. This required us to put money into sturdy logging and monitoring methods to higher perceive what is occurring through the execution and debug points successfully.
One other important perception emerged round late occasion dealing with—particularly, managing occasions with timestamps that fall inside a time-window’s boundaries however arrive after that window has closed. Amazon Managed Service for Apache Flink addresses this problem by its built-in watermarking mechanism. A watermark is a timestamp-based threshold that signifies when Flink ought to contemplate all occasions earlier than a selected time to have arrived. This permits the system to make knowledgeable choices about when to course of time-based operations like window aggregations. Watermarks circulate by the streaming pipeline, enabling Flink to trace the progress of occasion time processing even with out-of-order occasions.
Though watermarks present a mechanism to handle late information, they introduce challenges when coping with a number of enter streams working at completely different speeds. Watermarks work nicely when processing occasions from a single supply however can turn into problematic when becoming a member of streams with various velocities. It’s because they will result in unintended delays or untimely information discards. For instance, a sluggish stream can maintain again processing throughout all the pipeline, and an idle stream would possibly trigger untimely window closing. Our implementation required cautious tuning of watermark methods and allowable lateness parameters to steadiness processing timeliness with information completeness.
Our transition from Kafka Streams to Apache Flink proved smoother than initially anticipated. Groups with Java backgrounds and prior expertise with Kafka Streams discovered Flink’s programming mannequin intuitive and straightforward to make use of. The DataStream API gives acquainted ideas and patterns, and Flink’s extra superior options might be adopted incrementally as wanted. This gradual studying curve gave our builders the flexibleness to turn into productive rapidly, focusing first on core stream processing duties earlier than shifting on to extra superior ideas like state administration and late occasion processing.
The way forward for Flink in Nexthink
Actual-time alerting is now deployed to manufacturing and obtainable to our shoppers. A serious success of this mission was the truth that we efficiently launched a expertise as an alternative choice to Kafka streams, with little or no administration necessities, assured scalability, data-management flexibility, and comparable price.
The affect on the Nexthink alerting system was important as a result of we now not have a single evaluating alert by database polling. Subsequently, we’re already assessing the timeframe for onboarding different alerting use instances to real-time analysis with Flink. This may alleviate database load and also will present extra accuracy on the alert triggering.
But the affect of Flink isn’t restricted to the Nexthink alerting system. We now have a confirmed production-ready various for companies which might be restricted when it comes to scalability because of the variety of partitions of the matters they’re consuming. Thus, we’re actively evaluating the choice to transform extra companies to Flink to permit them to scale out extra flexibly.
Conclusion
Amazon Managed Service for Apache Flink has been transformative for our real-time alerting system at Nexthink. By dealing with the advanced infrastructure administration, AWS enabled our group to deploy a complicated streaming answer in lower than a month, retaining our give attention to delivering enterprise worth relatively than managing Flink clusters.
The capabilities of Flink have confirmed it to be greater than an alternative choice to Kafka Streams. It’s turn into a compelling first alternative for each new initiatives and present function refactoring. Windowed processing, late occasion administration, and stateful streaming operations have made advanced use instances remarkably simple to implement. As our growth groups proceed to discover Flink’s potential, we’re more and more assured that it’ll play a central function in Nexthink’s real-time information processing structure shifting ahead.
To get began with Amazon Managed Service for Apache Flink, discover the getting began sources and the hands-on workshop. To be taught extra about Nexthink’s broader journey with AWS, go to the weblog put up on Nexthink’s MSK-based structure.
In regards to the authors
Nikos Tragaras is a Principal Software program Architect at Nexthink with round 20 years of expertise in constructing distributed methods, from conventional architectures to trendy cloud-native platforms. He has labored extensively with streaming applied sciences, specializing in reliability and efficiency at scale. Captivated with programming, he enjoys constructing clear options to advanced engineering issues
Raphaël Afanyan is a Software program Engineer and Tech Lead of the Alerts group at Nexthink. Over time, he has labored on designing and scaling information processing methods and performed a key function in constructing Nexthink’s alerting platform. He now collaborates throughout groups to convey progressive product concepts to life, from backend structure to polished consumer interfaces.
Simone Pomata is a Senior Options Architect at AWS. He has labored enthusiastically within the tech trade for greater than 10 years. At AWS, he helps clients reach constructing new applied sciences day by day.
Subham Rakshit is a Senior Streaming Options Architect for Analytics at AWS based mostly within the UK. He works with clients to design and construct streaming architectures to allow them to get worth from analyzing their streaming information. His two little daughters preserve him occupied more often than not exterior work, and he loves fixing jigsaw puzzles with them. Join with him on LinkedIn.
Lorenzo Nicora works as a Senior Streaming Options Architect at AWS, serving to clients throughout EMEA. He has been constructing cloud-centered, data-intensive methods for over 25 years, working throughout industries each by consultancies and product corporations. He has used open supply applied sciences extensively and contributed to a number of initiatives, together with Apache Flink.
