jif d6c4c6aea4 Classify rollout read failures by reason and progress (#47565) ...

## Why

Rollout read metrics record the failure stage and I/O error kind, but these do not distinguish specific zstd failures, task join failures, or a busy reader, nor indicate whether any line was read before failure.

## What changed

Add bounded `reason` and `read_progress` labels to rollout read counters and duration metrics, captured at the first failure. Distinguish OS errors, reader-busy and task-join failures, and known zstd error categories, with `stream_error` as the fallback.

Record whether the failure occurred before or after the first line. Classify blocking-task join failures during both open and read. Keep error messages, file paths, and rollout contents out of metric labels.

GitOrigin-RevId: 6db302900f504bc2860504d81c18017adcef3efc

2026-09-23 15:01:19 +00:00

..

src

Classify rollout read failures by reason and progress (#47565)

2026-09-23 15:01:19 +00:00

BUILD.bazel

Extract rollout into its own crate (#15548)

2026-03-24 18:10:53 -07:00

Cargo.toml

Extract persisted history types into a dedicated crate (#37871)

2026-08-10 19:26:52 +00:00