thanos-io/thanos · error

could not calculate retention progress

Error message

could not calculate retention progress

What it means

rs.ProgressCalculate(ctx, retGroups) runs the RetentionProgressCalculator, which estimates how many blocks would be deleted by the configured retention policy per resolution. Failures are wrapped as 'could not calculate retention progress'. It is a metrics-only step in the periodic progress worker.

Solutions

1. If the inner error is 'context canceled', ignore it — it happens during graceful shutdown; check shutdown ordering in run.Group.
2. Inspect the wrapped error for the failing group and validate block metadata with 'thanos tools bucket inspect'.
3. Confirm retention flag values (--retention-resolution-raw etc.) parse as valid durations; fix invalid retention configuration.
4. Upgrade Thanos if the calculator errors on valid groups.

Example fix

// before
--retention-resolution-raw=14d --retention-resolution-5m=bd    # invalid duration
// after
--retention-resolution-raw=14d --retention-resolution-5m=1s    # or omit 5m retention

// Validate retention flags parse as durations before wiring the calculator
for _, d := range []string{rawRetention, res5mRetention, res1hRetention} {
    if _, err := time.ParseDuration(d); err != nil {
        log.Fatalf("invalid retention duration %q", d)
    }
}

if err := rs.ProgressCalculate(ctx, retGroups); err != nil {
    if ctx.Err() != nil {
        return nil // graceful shutdown
    }
    log.Errorf("could not calculate retention progress: %v", err)
    return nil
}

When it happens

Trigger: The retention calculator errors while applying retentionByResolution to the groups — typically when ctx is cancelled (shutdown) or when group/block state is inconsistent from earlier metadata problems.

Common situations: Most often seen as 'context canceled' during compactor shutdown while the progress loop is mid-calculation; also after bad grouping state caused by duplicate blocks.

Understand the failure class

Background: "Invalid value" and "allowed values are" config errors: what your library rejected and how to fix it — this error's family across 41 libraries.

Related errors

• raw resolution must be higher than the minimum block size…
• 5m resolution retention must be higher than the minimum…
• sync before retention
• retention failed
• could not calculate compaction progress

AI-assisted analysis of thanos-io/thanos@35b8b99117 (2026-09-07). Data as JSON: /api/errors/52d562f3ac08a268. Report an issue: GitHub.

Appendix: source

Thrown at cmd/thanos/compact.go:679

					}

					metas := sy.Metas()
					groups, err := grouper.Groups(metas)
					if err != nil {
						return errors.Wrapf(err, "could not group metadata for compaction")
					}

					if err = ps.ProgressCalculate(ctx, groups); err != nil {
						return errors.Wrapf(err, "could not calculate compaction progress")
					}

					retGroups, err := grouper.Groups(metas)
					if err != nil {
						return errors.Wrapf(err, "could not group metadata for retention")
					}

					if err = rs.ProgressCalculate(ctx, retGroups); err != nil {
						return errors.Wrapf(err, "could not calculate retention progress")
					}

					if !conf.disableDownsampling {
						groups, err = grouper.Groups(metas)
						if err != nil {
							return errors.Wrapf(err, "could not group metadata into downsample groups")
						}
						if err := ds.ProgressCalculate(ctx, groups); err != nil {
							return errors.Wrapf(err, "could not calculate downsampling progress")
						}
					}

					return nil
				})
			}, func(err error) {
				cancel()
			})
		}

View on GitHub (pinned to 35b8b99117)