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What is the most important feature an Express.js application can have? Maybe using sockets for real-time chats or GraphQL instead of REST APIs? Come on, tell me. What’s the most amazing, sexy, and hyped feature you have in your Express.js application? Want to guess what mine is? Optimal performance with minimal downtime. If your users can’t use your application, what’s the point of fancy features?

Making Node.js applications quick and sturdy is a tricky task to get right. Nailing the performance just right with the V8 engine Node.js is built on is not at all as simple as one would think. JavaScript is a dynamically typed language, where you let the interpreter assign types to variables. If you’re not careful this can lead to memory leaks. Node.js is at its essence a JavaScript runtime with

XDP or Express Data Path arises due to the pressing need for high-performance packet processing in the Linux kernel. Several kernel bypass techniques (DPDK being the most prominent one) aim to accelerate network operations by moving packet processing to user space. This means ditching the overhead induced by context switches, syscall transitions or IRQ requests between the kernel-user space bounda

Recent Linux kernel releases are equipped with a powerful Linux monitoring framework for kernel instrumentation. It has its roots in what historically was approached as BPF. What is BPF?BPF (Berkeley Packet Filter) is a very efficient network packet filtering mechanism aimed at avoiding the unnecessary user space allocations. It operates on network packet data directly in kernel land. The most fam

Containerized software is riding a wave of growth, according to latest RightScale survey.  At Sematext we see this growth trend via our Docker monitoring adoption and via Sematext Docker Agent popularity on Docker Hub, where it crossed 1M+ pulls line. This rapid rise of containers now makes Docker the top DevOps tool among those included in RightScale survey. Overall Docker adoption surged to 35 p

Monitor, visualize and get out of the box alerts on your complete Kubernetes infrastructure within minutes monitoringlogscontainerscloud Centralized visibility for your entire Kubernetes infrastructureGet metrics, logs and events from all Kubernetes componentsTrack your Kubernetes cluster performance and health with easeFast troubleshooting of individual control plane or node components and addons

More than two years ago we posted a recipe on how to centralize syslog in Elasticsearch in order to search and analyze them with Kibana, all by using only rsyslog. This works well, because rsyslog is fast and light, as we shown in later posts and recent presentations. This recipe is about tailing Apache HTTPD logs with rsyslog, parsing them into structured JSON documents, and forwarding them to El

Scalable and native container monitoring tools. Overcome challenges and get in-depth visibility into the health and performance of your entire distributed infrastructure. Try for Free Plans & Pricing Native & Lightweight Container Monitoring AgentSematext Agent runs as a lightweight container and collects all host and container metrics.Runs as DaemonSet on Kubernetes, Docker Swarm service, with Ra

Elasticsearch is near-realtime, in the sense that when you index a document, you need to wait for the next refresh for that document to appear in a search. Refreshing is an expensive operation and that is why by default it’s made at a regular interval, instead of after each indexing operation. This interval is defined by the index.refresh_interval setting, which can go either in Elasticsearch’s co

Many of our customers use AWS EC2. In the context of Elasticsearch consulting or support, one question we often get is: should we use AWS Elasticsearch Service instead of deploying Elasticsearch ourselves? The question is valid whether “self hosted” means in EC2, some other cloud or your own datacenter. As always, the answer is “it depends”, but in this post we’ll show how the advantages of AWS El

We’ve been doing a ton of work with ElasticSearch. Not long ago, we had a few situations where ElasticSearch would “eat” all the JVM heap memory we give it.  It was so hungry, we could not feed it enough memory to keep it happy.  It was insatiable.  After some troubleshooting and looking at SPM for ElasticSearch (btw. we released a new version of the SPM agent earlier this week, so if you don’t ha

“Solr or Elasticsearch?”…well, at least that is the common question we hear from Sematext’s consulting services clients and prospects. Which one is better, Solr or Elasticsearch? Which one is faster? Which one scales better? Which one is easier to manage? Which one should we use? Is there any advantage to migrating from Solr to Elasticsearch? – and the list goes on. These are all great questions,

The ability to search is a key feature of most modern applications. While encompassing huge amounts of data, they need to allow the end-user to find what they're searching for without delay. DevOps need to look beyond the traditional databases with complicated and non-user-friendly (even if smart and innovative) SQL query-based solutions to implement search functionality. That's where Apache Solr

In this post we discuss what HBase users should know about one of the internal parts of HBase: the Memstore. Understanding underlying processes related to Memstore will help to configure HBase cluster towards better performance. HBase MemstoreLet’s take a look at the write and read paths in HBase to understand what Memstore is, where how and why it is used. Memstore Usage in HBase Read/Write Paths