OpenTracing is a vendor neutral API and infrastructure for distributed tracing. Many OSS tracers just as Jaeger, OpenZipkin, Apache SkyWalking as well as commercial tools support OpenTracing APIs. Ideally, we can implement it once and have integrations for popular tracers like we have with metrics and prometheus.
I'm aware of
SOLR-9641 but HTrace has since retired from incubator for lack of activity so this is a fresh attempt at solving this problem.