cql-optimization: cross dc logic should (total_traffic-local)/total_traffic

Author: amnonh

grafana/scylla-cql-optimization.3.0.template.json

@@ -309,7 +309,7 @@
                         "description": "Cross DC traffic may cause additional latencies and network loads and in most cases, should be avoided.\n\nCross DC Read requests sources:\n- Consistency Level that is not LOCAL_XXX\n- Tables with read_repair_chance > 0\n\nNote:\n- If requests are supposed to be  DC local - verify client is using a DCAware policy and a LOCAL_XX consistency level",
                         "targets": [
                             {
-                                "expr": "100*sum(irate(scylla_storage_proxy_coordinator_reads_remote_node{instance=~\"[[node]]\",cluster=~\"$cluster|$^\", dc=~\"$dc\", datacenter=~\"$dc\", shard=~\"[[shard]]\"}[30s]))/sum(irate(scylla_storage_proxy_coordinator_reads_remote_node{instance=~\"[[node]]\",cluster=~\"$cluster|$^\", dc=~\"$dc\", shard=~\"[[shard]]\"}[30s]))",
+                                "expr": "100*(sum(irate(scylla_storage_proxy_coordinator_reads_remote_node{instance=~\"[[node]]\",cluster=~\"$cluster|$^\", dc=~\"$dc\", shard=~\"[[shard]]\"}[30s])) - sum(irate(scylla_storage_proxy_coordinator_reads_remote_node{instance=~\"[[node]]\",cluster=~\"$cluster|$^\", dc=~\"$dc\", datacenter=~\"$dc\", shard=~\"[[shard]]\"}[30s])))/sum(irate(scylla_storage_proxy_coordinator_reads_remote_node{instance=~\"[[node]]\",cluster=~\"$cluster|$^\", dc=~\"$dc\", shard=~\"[[shard]]\"}[30s]))",
                                 "format": "time_series",
                                 "intervalFactor": 1,
                                 "refId": "A"