Tag: Threshold Exceeded

Loki ingester encounters "object too large for cache" errors when attempting to store log entries exceeding memcache's configured size limit (typically 1MB). Large log lines remain in the ingester buffer causing continuous failed ingest attempts, pod health degradation, and eventual recycling.The accumulation of oversized entries can lead to buffer exhaustion and ingester instability.

Grafana Mimir's distributor rejects incoming Prometheus series when the number of labelnames on a single series exceeds the configured per-tenant limit. When this occurs, logscontain the message "received a series whose number of labels exceeds the limit" and theaffected samples are dropped. This typically arises from excessive or dynamic labeling inscrape targets or relabeling rules that generate many unique label names per series.To adjust the per-tenant limit, configure the distributor with`-validation.max-label-names-per-series`. When deploying via the `mimir-distributed` Helmchart, set `mimir.structuredConfig.limits.max_label_names_per_series` to a higher value(default is 30). Increase limits cautiously to avoid cardinality explosions and memorypressure. Prefer reducing label names at the source where possible.

Loki ingester reports memcached errors indicating out-of-memory conditions while cachingobjects, logging messages such as "SERVER_ERROR out of memory storing object". When thisoccurs, cache writes fail and can lead to degraded ingestion performance, retries, andincreased memory pressure on the ingester.