diff --git a/OpenTelemetryPlan/Phase9_taskList.md b/OpenTelemetryPlan/Phase9_taskList.md index e45c5bcd77..a172cd2e52 100644 --- a/OpenTelemetryPlan/Phase9_taskList.md +++ b/OpenTelemetryPlan/Phase9_taskList.md @@ -42,7 +42,7 @@ These metrics serve multiple external consumer categories identified during rese - In `src/libxrpl/nodestore/Database.cpp`, extend existing `beast::insight` registrations to add: - Gauge: `node_reads_total` (cumulative read operations) - - Gauge: `node_reads_hit` (cache-served reads) + - Gauge: `node_reads_hit` (fetches that found an object — not a cache hit; `fetchHitCount_` increments whatever served the fetch) - Gauge: `node_writes` (cumulative write operations) - Gauge: `node_written_bytes` (cumulative bytes written) - Gauge: `node_read_bytes` (cumulative bytes read) diff --git a/docker/telemetry/grafana/dashboards/ledger-data-sync.json b/docker/telemetry/grafana/dashboards/ledger-data-sync.json index 755d040a85..8d27906799 100644 --- a/docker/telemetry/grafana/dashboards/ledger-data-sync.json +++ b/docker/telemetry/grafana/dashboards/ledger-data-sync.json @@ -1481,7 +1481,7 @@ }, { "title": "NodeStore Read Latency (Bottleneck Discriminator)", - "description": "###### What this is:\n*The single measurement that separates the two ways a ledger sync stalls. Both modes look identical from the job queue -- the ledgerData lane sits at its concurrency limit of 3 with work waiting -- so lane occupancy on its own diagnoses nothing. Read latency does separate them, because the two modes load opposite ends of the storage path.*\n\n###### How it's computed:\n*Two views of the same quantity. Lifetime is the nodestore_state{metric=\"read_mean_us\"} gauge, which is total fetch microseconds divided by total fetches since process start, so it moves slowly and shows the run as a whole. Windowed is rate(node_reads_duration_us) / rate(node_reads_total) over the panel interval, so it reacts within one scrape. The axis is logarithmic because the two modes differ by more than an order of magnitude and a linear axis flattens the lower one.*\n\n###### Reading it:\n*Below about 10 microseconds per read means the backend is answering from the page cache and reads are not the constraint; if the lane is still full, the cost is on the write side -- check NuDB Writer Queue Depth next. Above about 100 microseconds per read, together with a high hit ratio on NuDB Cache Hit Ratio, means objects are being found but paid for with disk latency on every access. High latency with a low hit ratio is a different thing again: the working set does not fit and misses are scanning every backend. The threshold lines at 10 and 100 mark the two boundaries.*\n\n###### Healthy range:\n*Single-digit microseconds per read on a warm synced node, with lifetime and windowed close together.*\n\n###### Watch for:\n*Windowed rising well above lifetime: the recent window is much worse than the run average, which is the earliest reading of a cache that has just gone cold. A measured cold-read episode peaked at 223 microseconds and settled in the 13-35 range while still hitting 88 percent or better, and that shape hung a node for roughly 25 minutes. Also treat a flat 8-9 microsecond line during a stall as informative rather than reassuring -- it rules reads out and points at the write path.*\n\n###### Source:\n[nodestore/backend/NuDBFactory.cpp](https://github.com/XRPLF/rippled/blob/develop/src/libxrpl/nodestore/backend/NuDBFactory.cpp)\n\n###### Function:\n`Database::getFetchDurationUs / NuDB backend read path`", + "description": "###### What this is:\n*The single measurement that separates the two ways a ledger sync stalls. Both modes look identical from the job queue -- the ledgerData lane sits at its concurrency limit of 3 with work waiting -- so lane occupancy on its own diagnoses nothing. Read latency does separate them, because the two modes load opposite ends of the storage path.*\n\n###### How it's computed:\n*Two views of the same quantity. Lifetime is the nodestore_state{metric=\"read_mean_us\"} gauge, which is total fetch microseconds divided by total fetches since process start, so it moves slowly and shows the run as a whole. Windowed is rate(node_reads_duration_us) / rate(node_reads_total) over the panel interval, so it reacts within one scrape. The axis is logarithmic because the two modes differ by more than an order of magnitude and a linear axis flattens the lower one.*\n\n###### Reading it:\n*Below about 10 microseconds per read means the backend is answering from the page cache and reads are not the constraint; if the lane is still full, the cost is on the write side -- check NuDB Writer Queue Depth next. Above about 100 microseconds per read, together with a high found ratio on NuDB Read Found Ratio, means objects are being found but paid for with disk latency on every access. High latency with a low found ratio is a different thing again: the working set does not fit and misses are scanning every backend. The threshold lines at 10 and 100 mark the two boundaries.*\n\n###### Healthy range:\n*Single-digit microseconds per read on a warm synced node, with lifetime and windowed close together.*\n\n###### Watch for:\n*Windowed rising well above lifetime: the recent window is much worse than the run average, which is the earliest reading of a cache that has just gone cold. A measured cold-read episode peaked at 223 microseconds and settled in the 13-35 range while still hitting 88 percent or better, and that shape hung a node for roughly 25 minutes. Also treat a flat 8-9 microsecond line during a stall as informative rather than reassuring -- it rules reads out and points at the write path.*\n\n###### Source:\n[nodestore/backend/NuDBFactory.cpp](https://github.com/XRPLF/rippled/blob/develop/src/libxrpl/nodestore/backend/NuDBFactory.cpp)\n\n###### Function:\n`Database::getFetchDurationUs / NuDB backend read path`", "type": "timeseries", "gridPos": { "h": 8, diff --git a/docker/telemetry/grafana/dashboards/node-health.json b/docker/telemetry/grafana/dashboards/node-health.json index 2564a7195d..61379e639e 100644 --- a/docker/telemetry/grafana/dashboards/node-health.json +++ b/docker/telemetry/grafana/dashboards/node-health.json @@ -485,7 +485,7 @@ }, { "title": "NodeStore Throughput", - "description": "###### What this is:\n*Cumulative object-store read, cache-hit, and write operation counts.*\n\n###### How it's computed:\n*Current values of the read, cache-hit, and write counters, plotted as lines.*\n\n###### Reading it:\n*Steadily rising lines are normal; the slope reflects store activity.*\n\n###### Healthy range:\n*Reads and writes rising smoothly, with cache-hits tracking a good fraction of reads.*\n\n###### Watch for:\n*A sudden surge in reads or writes signals heavy back-end I/O, from sync, replay, or query load.*\n\n###### Source:\n[MetricsRegistry.cpp](https://github.com/XRPLF/rippled/blob/develop/src/xrpld/telemetry/MetricsRegistry.cpp)\n\n###### Function:\n`registerNodeStoreGauge`", + "description": "###### What this is:\n*Object-store read, found and write operation rates. The found series is `node_reads_hit`, which counts fetches that returned an object whatever served them, so it is not a cache-hit count.*\n\n###### How it's computed:\n*Per-second rates of the read, found and write counters, plotted as lines.*\n\n###### Reading it:\n*Steadily rising lines are normal; the slope reflects store activity.*\n\n###### Healthy range:\n*Reads and writes rising smoothly, with found tracking almost all reads on a node that has the data.*\n\n###### Watch for:\n*A sudden surge in reads or writes signals heavy back-end I/O, from sync, replay, or query load.*\n\n###### Source:\n[MetricsRegistry.cpp](https://github.com/XRPLF/rippled/blob/develop/src/xrpld/telemetry/MetricsRegistry.cpp)\n\n###### Function:\n`registerNodeStoreGauge`", "type": "timeseries", "gridPos": { "x": 0, @@ -512,7 +512,7 @@ "datasource": { "type": "prometheus" }, - "expr": "label_replace(rate(nodestore_state{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", xrpl_work_item=~\"$xrpl_work_item\", xrpl_branch=~\"$xrpl_branch\", xrpl_node_role=~\"$xrpl_node_role\", metric=\"node_reads_hit\"}[$__rate_interval]), \"series\", \"Reads Hit (cache)\", \"\", \"\")", + "expr": "label_replace(rate(nodestore_state{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", xrpl_work_item=~\"$xrpl_work_item\", xrpl_branch=~\"$xrpl_branch\", xrpl_node_role=~\"$xrpl_node_role\", metric=\"node_reads_hit\"}[$__rate_interval]), \"series\", \"Reads Found\", \"\", \"\")", "refId": "B" }, { @@ -542,8 +542,8 @@ } }, { - "title": "NodeStore Cache Hit Ratio", - "description": "###### What this is:\n*Cumulative object-store read, cache-hit, and write operation counts.*\n\n###### How it's computed:\n*Current values of the read, cache-hit, and write counters, plotted as lines.*\n\n###### Reading it:\n*Steadily rising lines are normal; the slope reflects store activity.*\n\n###### Healthy range:\n*Reads and writes rising smoothly, with cache-hits tracking a good fraction of reads.*\n\n###### Watch for:\n*A sudden surge in reads or writes signals heavy back-end I/O, from sync, replay, or query load.*\n\n###### Source:\n[MetricsRegistry.cpp](https://github.com/XRPLF/rippled/blob/develop/src/xrpld/telemetry/MetricsRegistry.cpp)\n\n###### Function:\n`registerNodeStoreGauge`", + "title": "NodeStore Read Found Ratio", + "description": "###### What this is:\n*Fraction of object-store fetches that found the object they asked for. This is not a cache hit ratio: `node_reads_hit` counts every fetch that returned an object, whatever served it, so a fetch that went all the way to disk still counts here.*\n\n###### How it's computed:\n*Rate of node_reads_hit divided by rate of node_reads_total over the panel interval.*\n\n###### Reading it:\n*Normally sits near 1.0 (100%) on any node that has the data, warm or cold. It does not fall when the page cache goes cold.*\n\n###### Healthy range:\n*Near 1.0. A ratio well below 1.0 means fetches are missing, which points at a gap in local history rather than at cache pressure.*\n\n###### Watch for:\n*Never read this panel on its own. A ~100% found ratio at over 100 microseconds per read is the cold-read signature, not a healthy cache: the data is found every time and paid for every time. Pair it with read latency.*\n\n###### Source:\n[nodestore/Database.cpp](https://github.com/XRPLF/rippled/blob/develop/src/libxrpl/nodestore/Database.cpp)\n\n###### Function:\n`Database::fetchNodeObject`", "type": "timeseries", "gridPos": { "x": 12, @@ -564,7 +564,7 @@ "type": "prometheus", "uid": "${DS_PROMETHEUS}" }, - "expr": "label_replace(rate(nodestore_state{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", xrpl_work_item=~\"$xrpl_work_item\", xrpl_branch=~\"$xrpl_branch\", xrpl_node_role=~\"$xrpl_node_role\", metric=\"node_reads_hit\"}[$__rate_interval]) / ignoring(metric) rate(nodestore_state{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", xrpl_work_item=~\"$xrpl_work_item\", xrpl_branch=~\"$xrpl_branch\", xrpl_node_role=~\"$xrpl_node_role\", metric=\"node_reads_total\"}[$__rate_interval]), \"series\", \"Cache Hit Ratio\", \"\", \"\")", + "expr": "label_replace(rate(nodestore_state{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", xrpl_work_item=~\"$xrpl_work_item\", xrpl_branch=~\"$xrpl_branch\", xrpl_node_role=~\"$xrpl_node_role\", metric=\"node_reads_hit\"}[$__rate_interval]) / ignoring(metric) rate(nodestore_state{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", xrpl_work_item=~\"$xrpl_work_item\", xrpl_branch=~\"$xrpl_branch\", xrpl_node_role=~\"$xrpl_node_role\", metric=\"node_reads_total\"}[$__rate_interval]), \"series\", \"Found Ratio\", \"\", \"\")", "refId": "A" } ], @@ -573,7 +573,7 @@ "displayName": "${__field.labels.series} [${__field.labels.service_instance_id} ${__field.labels.xrpl_branch} ${__field.labels.xrpl_node_role} ${__field.labels.xrpl_work_item}]", "unit": "percentunit", "custom": { - "axisLabel": "Operations / Sec", + "axisLabel": "Found Ratio", "drawStyle": "line", "lineWidth": 2, "fillOpacity": 10, @@ -1347,8 +1347,8 @@ } }, { - "title": "NuDB Storage Size", - "description": "###### What this is:\n*On-disk size of the NuDB object-store back end, in bytes.*\n\n###### How it's computed:\n*Current value of the NuDB storage-size gauge, plotted over time.*\n\n###### Reading it:\n*A smoothly growing line is normal; the slope is the data growth rate.*\n\n###### Healthy range:\n*Gradual growth consistent with retained ledger history.*\n\n###### Watch for:\n*A sudden jump in growth rate can indicate runaway storage or an unexpected back-fill.*\n\n###### Source:\n[MetricsRegistry.cpp](https://github.com/XRPLF/rippled/blob/develop/src/xrpld/telemetry/MetricsRegistry.cpp)\n\n###### Function:\n`registerStorageDetailGauge`", + "title": "NuDB Stored Bytes", + "description": "###### What this is:\n*Cumulative object-payload bytes this process has written to the NuDB object-store back end. Despite the metric name, this is not the size of the store on disk.*\n\n###### How it's computed:\n*Current value of the nudb_bytes gauge, plotted over time. It observes getStoreSize(), the same accessor node_written_bytes uses, so the two series are equal and their ratio is a constant 1.0 rather than a write-amplification measure.*\n\n###### Reading it:\n*A smoothly growing line is normal; the slope is the write rate. It excludes NuDB's keys, bucket padding and log, and it restarts from zero with the process while the files on disk do not.*\n\n###### Healthy range:\n*Gradual growth consistent with ledger data being stored.*\n\n###### Watch for:\n*A sudden jump in growth rate can indicate runaway storage or an unexpected back-fill. Do not use this panel to size the store on disk or to plan disk capacity; no metric reports on-disk size today, so check the filesystem directly.*\n\n###### Source:\n[MetricsRegistry.cpp](https://github.com/XRPLF/rippled/blob/develop/src/xrpld/telemetry/MetricsRegistry.cpp)\n\n###### Function:\n`registerStorageDetailGauge`", "type": "timeseries", "gridPos": { "h": 8, @@ -1368,7 +1368,7 @@ "datasource": { "type": "prometheus" }, - "expr": "label_replace(storage_detail{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", xrpl_work_item=~\"$xrpl_work_item\", xrpl_branch=~\"$xrpl_branch\", xrpl_node_role=~\"$xrpl_node_role\", metric=\"nudb_bytes\"}, \"series\", \"NuDB Size\", \"\", \"\")" + "expr": "label_replace(storage_detail{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", xrpl_work_item=~\"$xrpl_work_item\", xrpl_branch=~\"$xrpl_branch\", xrpl_node_role=~\"$xrpl_node_role\", metric=\"nudb_bytes\"}, \"series\", \"NuDB Stored Bytes\", \"\", \"\")" } ], "fieldConfig": { @@ -1376,7 +1376,7 @@ "displayName": "${__field.labels.series} [${__field.labels.service_instance_id} ${__field.labels.xrpl_branch} ${__field.labels.xrpl_node_role} ${__field.labels.xrpl_work_item}]", "unit": "decbytes", "custom": { - "axisLabel": "Size", + "axisLabel": "Stored Bytes", "drawStyle": "line", "lineWidth": 2, "fillOpacity": 10,