Summary meta key goes missing

[lightindigo]

While using PromPhP's summary with APCng we get "Meta info missing for meta key: prom:summary:" from time to time.

As far as I see it really goes missing after some time. Key when present definitely has no timeout

APC is configured ttl = 0, memory capacity is far from depletion (like 200k/32M)

The metric itself is written something like this

$summary = $registry->getOrRegisterSummary(
    self::APP_NAMESPACE,
    MetricNames::DB_QUERIES_PER_REQUEST,
    'Db requests per request',
    [],
    600,
    self::DEFAULT_QUANTILES
);
$summary->observe($numRequests);

[votetake]

Hello team, any news?

[pyanukovich]

Is there some information about meta info missing for the meta key: prom:summary: apc with ttl = 0?

[pyanukovich]

Seems similar to https://github.com/PromPHP/prometheus_client_php/issues/126