Chapter 3. Feature enhancements Cryostat 2.4 includes feature enhancements that build upon the Cryostat 2.3 offerings. Topology view enhancements for displaying Cryostat agents In the Topology view of the Cryostat web console, Cryostat agents are now displayed with the Cryostat icon. This helps to differentiate the Cryostat agents from JMX targets, which are still displayed with the OpenJDK Duke icon. Topology and Dashboard views display additional target details The Topology and Dashboard views of the Cryostat web console now display the following additional types of information for your target JVMs: Operating system name Total physical memory Total swap space Class path Library paths Input arguments System properties Note You can view this information in either of the following ways: In the Topology panel, click the twistie ( > ) icons to expand down to a target endpoint and then click the Details tab for this endpoint. In the Dashboard panel, add the Target JVM Details card to the dashboard. Auomated Analysis enhancements for JFR recordings In the Cryostat 2.4 web console, the Automated Analysis information for a JFR recording reuses components from the Automated Analysis dashboard card. This supersedes the behavior in releases where Automated Analysis data provided a more limited set of information. Note To view Automated Analysis information for a JFR recording, open any panel that includes a list of recordings and click the twistie ( > ) icon to the recording you are interested in. Parameter enhancements for restarting JFR recordings When creating a JFR flight recording, the Cryostat server typically rejects requests to create a recording if another recording with the same name already exists on the same target. Clients can modify this behavior by specifying a request parameter to restart the recording. In releases, clients could include a restart parameter in requests to create a recording. The restart parameter accepted true or false values and was set to false by default. If the client request included a restart=false setting, the Cryostat server rejected the request if another recording with the same name already existed. If the client request included a restart=true setting, the Cryostat server would stop, delete, and recreate any existing recording with the same name. Cryostat 2.4 introduces a new replace parameter, which supersedes the restart parameter that was available in releases. The replace parameter accepts always , never , or stopped values. In this situation, a setting of replace=always matches the old restart=true behavior, and a setting of replace=never matches the old restart=false behavior. The replace=stopped setting provides a third type of behavior, by instructing the server to recreate a recording with the same name only if the existing recording is in a STOPPED state. Otherwise, if the client request includes a replace=stopped setting, but an existing recording with the same name is in another state such as RUNNING , the server rejects the request. This enhancement helps to avoid situations where enabling automated rules to recreate JFR recordings might lead to the loss of non-archived data for recordings that are not in a STOPPED state. Enhanced error and warning messages Cryostat 2.4 includes enhancements to various error and warning messages.

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