kvserver, storage: add bytes compressed/decompressed metrics

The motivation for these metrics is to enable estimating the CPU usage
impact of switching to a stronger compression method (which applies
only to L5/L6 data/value blocks).

Epic: none
Release note: None

Author: RaduBerinde

pkg/kv/kvserver/metrics.go

@@ -1236,6 +1236,54 @@ storage.initial_stats_complete becomes true.
 		Measurement: "Ratio",
 		Unit:        metric.Unit_CONST,
 	}
+	metaBytesCompressedL5Data = metric.Metadata{
+		Name:        "storage.bytes-compressed.l5.data",
+		Help:        "Total number of logical bytes compressed for L5 data blocks.",
+		Measurement: "Bytes",
+		Unit:        metric.Unit_BYTES,
+	}
+	metaBytesDecompressedL5Data = metric.Metadata{
+		Name:        "storage.bytes-decompressed.l5.data",
+		Help:        "Total number of logical bytes decompressed for L5 data blocks.",
+		Measurement: "Bytes",
+		Unit:        metric.Unit_BYTES,
+	}
+	metaBytesCompressedL5Values = metric.Metadata{
+		Name:        "storage.bytes-compressed.l5.values",
+		Help:        "Total number of logical bytes compressed for L5 value blocks.",
+		Measurement: "Bytes",
+		Unit:        metric.Unit_BYTES,
+	}
+	metaBytesDecompressedL5Values = metric.Metadata{
+		Name:        "storage.bytes-decompressed.l5.values",
+		Help:        "Total number of logical bytes decompressed for L5 value blocks.",
+		Measurement: "Bytes",
+		Unit:        metric.Unit_BYTES,
+	}
+	metaBytesCompressedL6Data = metric.Metadata{
+		Name:        "storage.bytes-compressed.l6.data",
+		Help:        "Total number of logical bytes compressed for L6 data blocks.",
+		Measurement: "Bytes",
+		Unit:        metric.Unit_BYTES,
+	}
+	metaBytesDecompressedL6Data = metric.Metadata{
+		Name:        "storage.bytes-decompressed.l6.data",
+		Help:        "Total number of logical bytes decompressed for L6 data blocks.",
+		Measurement: "Bytes",
+		Unit:        metric.Unit_BYTES,
+	}
+	metaBytesCompressedL6Values = metric.Metadata{
+		Name:        "storage.bytes-compressed.l6.values",
+		Help:        "Total number of logical bytes compressed for L6 value blocks.",
+		Measurement: "Bytes",
+		Unit:        metric.Unit_BYTES,
+	}
+	metaBytesDecompressedL6Values = metric.Metadata{
+		Name:        "storage.bytes-decompressed.l6.values",
+		Help:        "Total number of logical bytes decompressed for L6 value blocks.",
+		Measurement: "Bytes",
+		Unit:        metric.Unit_BYTES,
+	}
 )
 
 var (
@@ -3115,6 +3163,13 @@ type StoreMetrics struct {
 	CompressionUnknownBytes *metric.Gauge
 	CompressionOverallCR    *metric.GaugeFloat64
 
+	BytesCompressed, BytesDecompressed struct {
+		L5, L6 struct {
+			Values *metric.Counter
+			Data   *metric.Counter
+		}
+	}
+
 	categoryIterMetrics                pebbleCategoryIterMetricsContainer
 	categoryDiskWriteMetrics           pebbleCategoryDiskWriteMetricsContainer
 	ValueSeparationBytesReferenced     *metric.Gauge
@@ -3872,6 +3927,8 @@ func newStoreMetrics(histogramWindow time.Duration) *StoreMetrics {
 		CompressionUnknownBytes: metric.NewGauge(metaCompressionUnknownBytes),
 		CompressionOverallCR:    metric.NewGaugeFloat64(metaCompressionOverallCR),
 
+		// BytesCompressed, BytesDecompressed are initialized below.
+
 		categoryDiskWriteMetrics: pebbleCategoryDiskWriteMetricsContainer{
 			registry: storeRegistry,
 		},
@@ -4212,6 +4269,16 @@ func newStoreMetrics(histogramWindow time.Duration) *StoreMetrics {
 		ClosedTimestampPolicyChange:       metric.NewCounter(metaClosedTimestampPolicyChange),
 		ClosedTimestampLatencyInfoMissing: metric.NewCounter(metaClosedTimestampLatencyInfoMissing),
 	}
+
+	sm.BytesCompressed.L5.Data = metric.NewCounter(metaBytesCompressedL5Data)
+	sm.BytesCompressed.L5.Values = metric.NewCounter(metaBytesCompressedL5Values)
+	sm.BytesCompressed.L6.Data = metric.NewCounter(metaBytesCompressedL6Data)
+	sm.BytesCompressed.L6.Values = metric.NewCounter(metaBytesCompressedL6Values)
+	sm.BytesDecompressed.L5.Data = metric.NewCounter(metaBytesDecompressedL5Data)
+	sm.BytesDecompressed.L5.Values = metric.NewCounter(metaBytesDecompressedL5Values)
+	sm.BytesDecompressed.L6.Data = metric.NewCounter(metaBytesDecompressedL6Data)
+	sm.BytesDecompressed.L6.Values = metric.NewCounter(metaBytesDecompressedL6Values)
+
 	sm.categoryIterMetrics.init(storeRegistry)
 
 	storeRegistry.AddMetricStruct(sm)
@@ -4378,6 +4445,15 @@ func (sm *StoreMetrics) updateEngineMetrics(m storage.Metrics) {
 	// ratio; we estimate it from the data we do have.
 	sm.CompressionOverallCR.Update(overall.CompressionRatio())
 
+	sm.BytesCompressed.L5.Values.Update(int64(m.CompressionCounters.LogicalBytesCompressed.L5.ValueBlocks))
+	sm.BytesCompressed.L5.Data.Update(int64(m.CompressionCounters.LogicalBytesCompressed.L5.DataBlocks))
+	sm.BytesCompressed.L6.Values.Update(int64(m.CompressionCounters.LogicalBytesCompressed.L6.ValueBlocks))
+	sm.BytesCompressed.L6.Data.Update(int64(m.CompressionCounters.LogicalBytesCompressed.L6.DataBlocks))
+	sm.BytesDecompressed.L5.Values.Update(int64(m.CompressionCounters.LogicalBytesDecompressed.L5.ValueBlocks))
+	sm.BytesDecompressed.L5.Data.Update(int64(m.CompressionCounters.LogicalBytesDecompressed.L5.DataBlocks))
+	sm.BytesDecompressed.L6.Values.Update(int64(m.CompressionCounters.LogicalBytesDecompressed.L6.ValueBlocks))
+	sm.BytesDecompressed.L6.Data.Update(int64(m.CompressionCounters.LogicalBytesDecompressed.L6.DataBlocks))
+
 	sm.categoryIterMetrics.update(m.CategoryStats)
 	sm.categoryDiskWriteMetrics.update(m.DiskWriteStats)