Published on feb 10, 2023
Grafana has released Grafana Tempo 2.0, which introduces TraceQL query language and support for Apache Parquet. Grafana Tempo is an open-source tracing backend that supports object storage. Using TraceQL and the Apache Parquet format, improved search times can be achieved and queries can be aligned with traces.
TraceQL is based on existing query languages such as PromQL and LogQL. Traces can be selected based on span and resource attributes, timing, and duration. TraceQL queries are expressions that are evaluated one trace at a time.
Queries consist of a series of expressions chained together into a pipeline. Each expression in the pipeline selects or discards spansets from inclusion in the results. As an example, the following query will select traces where the spans have an http.status_code between 200 and 299 and there are more than two matching spans within the trace.
Traces represent the journey taken by a request through the system under observation. A trace consists of one or more spans that represent units of work. There is a start time relative to the start of the trace, a duration, and a name for the operation associated with the span.
In TraceQL, there are two types of span data: intrinsics and attributes. Spans have intrinsic fields, which include things such as the status, duration, and name of the span. The attribute fields are derived from the span and can be customized. The query [ span.http.method = “GET” ] uses attribute fields on the span to return traces using the HTTP GET method.
Additionally, this release includes the aggregators count and sum. A count of spans within a spanset can be provided by count, while an average of an attribute or intrinsic for a spanset can be obtained by average.
In this release, Apache Parquet is introduced as the default backend storage format. The Apache Parquet format is an open-source, column-oriented data file format.
Tempo 2.0 includes a new Parquet block that is enabled by default and required in order to make use of the new TempoQL query language. When enabled, Tempo will begin writing data in the Parquet format, but existing data will remain unchanged. It is possible to disable the Parquet format and instead use the original v2 block format.
Tempo 2.0 is an open-source application licensed under the AGPL-3.0 license. According to Elliott, Grafana 9.4 provides the best TraceQL experience.
