{"version":"2.1.222","anchor":"telemetry-retry-batches-can-persist-as-v5-streams","canonical_anchor":"telemetry-retry-batches-can-persist-as-v5-streams","heading":"Telemetry retry batches can persist as v5 streams","tier":"internal","area":"Telemetry","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.222\/e\/telemetry-retry-batches-can-persist-as-v5-streams","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.222","markdown":"### Telemetry retry batches can persist as v5 streams\n\nFailed telemetry batches can be stored and retried differently, but only with a backend that nothing here supplies.\n\n**What**\n\nThe first-party event exporter gained a path that stores failed-event batches as append-only v5 streams keyed by run id and retries earlier runs in the background.\n\n**Details**\n\n- Leftover flat JSON batches are migrated into streams using deterministic record ids of the form `flat-migration.<index>.<hash>`, and the flat file is deleted afterwards.\n- Only taken when a storageV5 backend is passed to the exporter; what enables that backend could not be determined.\n- Without a v5 backend the existing flat-file path is unchanged.\n\n**Evidence**\n\n`1P event logging: failed to persist failed-event queue to v5 stream`\n\n- Area: Telemetry\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 2\/5\n- Present in the build but not switched on"}