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FusionReactor glossary

FR glossary is a work in progress. We will continue to periodically update the list.


Archive Metrics | The rendering of FusionReactor log files to enable historic troubleshooting.

application | A web application (web app) is an application program that is stored on a remote server and delivered over the internet through a browser interface. Web services are web apps by definition and many, although not all, websites contain web apps.



CommandBox | CommandBox is a standalone, native tool for Windows, Mac, and Linux that provides you with a Command Line Interface (CLI) for developer productivity, tool interaction, package management, embedded CFML server, application scaffolding, and some ASCII art.

compression | Involves the automatic compression of responses before they are sent to the browser to reduce network requirements at the cost of CPU usage.

CPU (%) | The CPU load of two types: your server, and your application server instance.

Crash Protection | Crash protection gives you the ability to alert when the application server is experiencing issues and prevent application servers from crashing.

Custom Metrics |


Distributed trace | A trace which describes a request/transaction involving multiple instances/services.


Enterprise dashboard | The Enterprise dashboard allows you to monitor more than one server instances easily, in an easy to read graphical dashboard display. It is a powerful tool providing an overview of your infrastructure from one location.

Enterprise Scripting | FusionReactor Enterprise Scripting, enhances FusionReactor's Enterprise Monitoring to trigger configurable scripts when a server's responsiveness status changes.

Event Snapshot | Event Snapshots are generated for specific events that may occur whilst FusionReactor monitors your application. The Event Snapshot displays source code, scope variables, stack trace and logging information at the point the problem occurs; providing everything you need to isolate the issue as quickly and efficiently as possible.

exporter | An exporter is a software application that writes out a data file in a format different from its native format. It does this via special algorithms (such as filters ). An exporter often is not an entire program by itself, but an extension to another program, implemented as a plug-in.


FR | FusionReactor

FRAM | FusionReactor Administration Manager

FRAPI | FusionReactor API

FRUID | FusionReactor unique identifier


GRUID | Globally unique identifier


heterogeneous systems | Traditionally, heterogeneous computing refers to a system that uses more than one type of computing cores, such as CPU, GPU, DPU, VPU, FPGA, or ASIC.


instance | The host the service is running on.

instrumentation | The act of instrumenting code so that it generates spans.


JDBC activity | The number of JDBC requests complete and active at a given time.  

JDBC time | The average time of all completed and active JDBC requests at a given time.

Job | Is typically the name of the service you are running.

JRE | Java Runtime Environment


Kubernetes | Kubernetes is a platform for managing containers.


log monitoring | Log monitoring is the process of collating and centralising logs, or data files, from various applications across your network to detect malicious activity.


Memory (MB) | The memory usage of your server, showing three types: Max memory, Allocated memory, and Used memory.



pipeline | A pipeline is an ordered set of processes applied to a filtered subset of logs, which happens after the collection of logs but before indexing.

Profiler | The profiler is designed to help you identify performance bottlenecks in your production environment with very low overhead. FusionReactor has numerous profilers including: code profiler, thread profiler, CPU profiler and more.


Sampling | The decision to process/export an event/action as a span.

Span | The representation of a single event/action containing related information.

Span attribute | A key-value property, belonging to a span, describing information about the event/action.

Span child | The span generated from a separate, preceding span describing an event/action.

Span duration | The duration of the event/action described by the span.

Span event | An interesting event that occurred during the span. May contain information/logs which describe it.

Span kind | A categorization to describe span relationships eg: Internal, Server, Client, Producer, Consumer.

Span link | A link from one span to another which indicates that they are related. The linked spans are usually on separate traces.

Span name | A name given to the span for identification/descriptive purposes. The default name of FusionReactor spans depends on the transaction flavour. If a name can't be found then the transaction flavour is used as the name.

Span parent | The span which generated a separate, succeeding span describing an event/action.

Span status | The status of the span. One of unset/OK/error.

Subflavor | FusionReactor monitors many requests and transactions of different types. Through the use of Transit, FusionReactor is able to split these requests and transactions into their different categories known as flavors. It is possible to break down these flavors even further to sub-categories based on the different purposes of the request, known as subflavors. Examples include GET, POST, DELETE, CREATE, UPDATE etc. PUT CONNECT


Time Frame | This control allows you to select different time frames to view.

Trace | A trace represents a series of events/actions (spans) which make up one whole request/transaction. |

Trace context | Context which describes a trace.

Trace context propagation | The act of propagating/passing trace information to generated child spans, ensuring that the information is propagated throughout the entire trace.

Trace ID | Each trace has a unique ID which is used to join related spans together.

Traceparent Header | A header which is used to pass the trace parent to downstream instances/services. Downstream instances/services will use this as the span parent of generated spans, connecting the two instances/services to the same trace.

Tracestate Header | A header used to pass information regarding the state of the trace.


UEM | User Experience Management

Unsampled ITT | If a span was slow or it errored, the span can be considered an Interesting Transaction (ITT). If it was decided, at the span's creation, that the span wasn't to be sampled, there's a chance that FusionReactor will change this decision and sample/export it. This does not affect the sample state of parent and child spans


Web Request | A web request is a request made by a client, such as a web browser, to a server in order to retrieve a web page or other resource.

WebRequest activity | The number of requests completed and active at a given time.

WebRequest time | The average time of all completed and active requests at a given time.