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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 fa

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

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

Catch regressions before they get deployed to production through automated tests in your CI/CD pipeline!  Learn more

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

“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,

In this post we’ll explain the usage of FuzzyRowFilter which can help in many situations where secondary indexes solutions seems to be the only choice to avoid full table scans. BackgroundWhen it comes to HBase the way you design your row key affects everything. It is a common pattern to have composite row key which consists of several parts, e.g. userId_actionId_timestamp. This allows for fast fe

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