Skip to main content
Redhat Developers  Logo
  • Products

    Featured

    • Red Hat Enterprise Linux
      Red Hat Enterprise Linux Icon
    • Red Hat OpenShift AI
      Red Hat OpenShift AI
    • Red Hat Enterprise Linux AI
      Linux icon inside of a brain
    • Image mode for Red Hat Enterprise Linux
      RHEL image mode
    • Red Hat OpenShift
      Openshift icon
    • Red Hat Ansible Automation Platform
      Ansible icon
    • Red Hat Developer Hub
      Developer Hub
    • View All Red Hat Products
    • Linux

      • Red Hat Enterprise Linux
      • Image mode for Red Hat Enterprise Linux
      • Red Hat Universal Base Images (UBI)
    • Java runtimes & frameworks

      • JBoss Enterprise Application Platform
      • Red Hat build of OpenJDK
    • Kubernetes

      • Red Hat OpenShift
      • Microsoft Azure Red Hat OpenShift
      • Red Hat OpenShift Virtualization
      • Red Hat OpenShift Lightspeed
    • Integration & App Connectivity

      • Red Hat Build of Apache Camel
      • Red Hat Service Interconnect
      • Red Hat Connectivity Link
    • AI/ML

      • Red Hat OpenShift AI
      • Red Hat Enterprise Linux AI
    • Automation

      • Red Hat Ansible Automation Platform
      • Red Hat Ansible Lightspeed
    • Developer tools

      • Red Hat Trusted Software Supply Chain
      • Podman Desktop
      • Red Hat OpenShift Dev Spaces
    • Developer Sandbox

      Developer Sandbox
      Try Red Hat products and technologies without setup or configuration fees for 30 days with this shared Openshift and Kubernetes cluster.
    • Try at no cost
  • Technologies

    Featured

    • AI/ML
      AI/ML Icon
    • Linux
      Linux Icon
    • Kubernetes
      Cloud icon
    • Automation
      Automation Icon showing arrows moving in a circle around a gear
    • View All Technologies
    • Programming Languages & Frameworks

      • Java
      • Python
      • JavaScript
    • System Design & Architecture

      • Red Hat architecture and design patterns
      • Microservices
      • Event-Driven Architecture
      • Databases
    • Developer Productivity

      • Developer productivity
      • Developer Tools
      • GitOps
    • Secure Development & Architectures

      • Security
      • Secure coding
    • Platform Engineering

      • DevOps
      • DevSecOps
      • Ansible automation for applications and services
    • Automated Data Processing

      • AI/ML
      • Data Science
      • Apache Kafka on Kubernetes
      • View All Technologies
    • Start exploring in the Developer Sandbox for free

      sandbox graphic
      Try Red Hat's products and technologies without setup or configuration.
    • Try at no cost
  • Learn

    Featured

    • Kubernetes & Cloud Native
      Openshift icon
    • Linux
      Rhel icon
    • Automation
      Ansible cloud icon
    • Java
      Java icon
    • AI/ML
      AI/ML Icon
    • View All Learning Resources

    E-Books

    • GitOps Cookbook
    • Podman in Action
    • Kubernetes Operators
    • The Path to GitOps
    • View All E-books

    Cheat Sheets

    • Linux Commands
    • Bash Commands
    • Git
    • systemd Commands
    • View All Cheat Sheets

    Documentation

    • API Catalog
    • Product Documentation
    • Legacy Documentation
    • Red Hat Learning

      Learning image
      Boost your technical skills to expert-level with the help of interactive lessons offered by various Red Hat Learning programs.
    • Explore Red Hat Learning
  • Developer Sandbox

    Developer Sandbox

    • Access Red Hat’s products and technologies without setup or configuration, and start developing quicker than ever before with our new, no-cost sandbox environments.
    • Explore Developer Sandbox

    Featured Developer Sandbox activities

    • Get started with your Developer Sandbox
    • OpenShift virtualization and application modernization using the Developer Sandbox
    • Explore all Developer Sandbox activities

    Ready to start developing apps?

    • Try at no cost
  • Blog
  • Events
  • Videos

Filter unwanted notifications in Cryostat 2.1

May 26, 2022
Andrew Azores
Related topics:
ContainersJavaKubernetes
Related products:
Red Hat OpenShift Container Platform

Share:

    Cryostat has always issued notifications when monitoring Java applications with Java Flight Recorder (JFK). Version 2.1 of Cryostat has a new implementation and interface for notifications that increases the amount of information offered, enhances the user's control over what is displayed, and improves Cryostat performance.

    Cryostat interface

    Thanks to a new WebSocket interface, Cryostat issues notifications for events that were not reported before. Thus, by default, many more notifications are reported to the user. For instance, the new automated rules feature adds rules to lots of instances at once and emits notifications when each rule is created or deleted, as well as when a rule starts a recording, copies a recording to archive, or prunes an old recording from the archive. The volume of notifications could become especially daunting, as Figure 1 illustrates.

    Cryostat can deliver an enormous number of notifications.
    Figure 1: Cryostat can deliver an enormous number of notifications.

    To deal with this problem, Cryostat 2.1 gives users the ability to enable and disable the notifications they receive through a new Settings page (Figure 2). The user can select notifications by category or, with a single click, enable or disable all notifications.

    The Settings view in Cryostat 2.1 includes a Notifications widget with toggles for each notification category.
    Figure 2: The Settings view in Cryostat 2.1 includes a Notifications widget with toggles for each notification category.

    For example, to disable all notifications that might be emitted by the background activities of the automated rules, toggle off the following categories:

    • Recording Created (emitted when an automated rule creates a new recording on a target)
    • Recording Saved (emitted when an automated rule copies an active recording to the archives)
    • Archived Recording Deleted (emitted when an automated rule trims old copies from the archives)

    Implementation and performance

    Cryostat uses a WebSocket connection between the Cryostat backend and the web client running in your browser to display notifications when various actions or state changes occur. In Cryostat 2.1, a WebSocket notification is emitted for all conceptual actions and state changes that can occur, whereas previous versions of Cryostat did not include notifications for some types of action or state change. Formatting is also more consistent now, with a detailed title and description for each notification type.

    When a notification category is disabled, the messages are still sent over the WebSocket connection, but the toast notification in the web client simply isn't displayed. The user's chosen settings are entirely on the web client side and are persisted in the browser's local storage. The web client still receives and holds the notification information in memory. Therefore, if you re-enable a notification category, any previously emitted notifications in that category will still be available for you to read. This way, Cryostat avoids cluttering the user interface with notifications while still preserving a log of actions and state changes for inspection if needed.

    Note: The notification categories do not distinguish between actions performed by an automated rule and those performed by an interactive user by another client via API requests. If you disable these notifications, they will be disabled for all cases, not only when an automated rule performs them.

    Web client performance has also been improved by using notifications to update the state of resources such as active recordings, archived recordings, and templates. For example, when an active recording is deleted, the web client now uses the corresponding notification from the backend to update the active recordings list by deleting the recording in question. Other state updates work in a similar manner. Previously, this workflow would have required sending an HTTP GET request to the backend to get the entire, updated list of active recordings and using this list to fully replace the outdated list displayed to the user. Now the web client simply updates a single deleted recording entry.

    Conclusion

    Cryostat's notification process is much better structured and richer in version 2.1. It requires a bit more preparation in your browser to get the notifications you want and exclude the many others you might find distracting. But consistency and performance improvements create a better user interface.

    Last updated: November 6, 2023

    Related Posts

    • How to log into Cryostat 2.1 on OpenShift: SSO for all

    • How to build automated JFR rules with Cryostat 2.1's new UI

    • How to organize JFR data with recording labels in Cryostat 2.1

    • Manage JFR across instances with Cryostat and GraphQL

    • Manage JMX credentials on Kubernetes with Cryostat 2.1

    Recent Posts

    • Meet the Red Hat Node.js team at PowerUP 2025

    • How to use pipelines for AI/ML automation at the edge

    • What's new in network observability 1.8

    • LLM Compressor: Optimize LLMs for low-latency deployments

    • How to set up NVIDIA NIM on Red Hat OpenShift AI

    What’s up next?

    The microservice architectural approach is more than just about technology: It reaches into the foundation of your organization to allow you to build truly scalable, adaptive, complex systems that help a business adapt to rapidly changing competitive markets. In Microservices for Java Developers, you'll get a hands-on introduction to frameworks and containers through a handful of familiar patterns.

    Get the free e-book
    Red Hat Developers logo LinkedIn YouTube Twitter Facebook

    Products

    • Red Hat Enterprise Linux
    • Red Hat OpenShift
    • Red Hat Ansible Automation Platform

    Build

    • Developer Sandbox
    • Developer Tools
    • Interactive Tutorials
    • API Catalog

    Quicklinks

    • Learning Resources
    • E-books
    • Cheat Sheets
    • Blog
    • Events
    • Newsletter

    Communicate

    • About us
    • Contact sales
    • Find a partner
    • Report a website issue
    • Site Status Dashboard
    • Report a security problem

    RED HAT DEVELOPER

    Build here. Go anywhere.

    We serve the builders. The problem solvers who create careers with code.

    Join us if you’re a developer, software engineer, web designer, front-end designer, UX designer, computer scientist, architect, tester, product manager, project manager or team lead.

    Sign me up

    Red Hat legal and privacy links

    • About Red Hat
    • Jobs
    • Events
    • Locations
    • Contact Red Hat
    • Red Hat Blog
    • Inclusion at Red Hat
    • Cool Stuff Store
    • Red Hat Summit

    Red Hat legal and privacy links

    • Privacy statement
    • Terms of use
    • All policies and guidelines
    • Digital accessibility

    Report a website issue