When we use prometheus to monitor our dgraph, we find that the metrics such as dgraph_lru_hits_total,dgraph_lru_miss_total etc… are missing in the debug/prometheus_metrics endpoint.
Our dgraph version is 1.0.16
There is no LRU cache in Dgraph for now since Dgraph v1.0.12. We plan on bringing back a cache by integrating Ristretto in a future version of Dgraph. Until then, the cache metrics will not be available.
This is to say, the config lru_mb in alpha node does not work？
dgraph alpha --my=server:7080 --lru_mb=2048
Yes, this flag is still required as it is a temporary change. The default will always be to require this flag. So we didn’t remove it. However, I believe it will not be mandatory in this next release and RCs (not 100% sure, I remember there is a commit about it) until we integrate Ristretto. That then the flag will be mandatory again.