Issue #12: Complete Performance Benchmark Integration

Makefile

@@ -79,7 +79,7 @@ build-legacy:
 # Run the application (new CLI)
 run: docker-up
 	@echo "Waiting for Neo4j to be ready..."
-	@sleep 15
+	@sleep 30
 	@echo "Starting application..."
 	go run cmd/sql-graph-visualizer/main.go serve
 

cmd/main.go

@@ -274,6 +274,7 @@ func main() {
 			performanceServices.GraphMapper,
 			performanceServices.RealtimeMonitor,
 			performanceServices.PSAdapter,
+			neo4jRepo,
 		)
 		performanceHandlers.RegisterRoutes(router)
 		logrus.Info("Performance API routes registered")

go.mod

@@ -6,7 +6,7 @@ toolchain go1.26.4
 
 require (
 	github.com/99designs/gqlgen v0.17.91
-	github.com/go-sql-driver/mysql v1.9.3
+	github.com/go-sql-driver/mysql v1.10.0
 	github.com/google/uuid v1.6.0
 	github.com/gorilla/mux v1.8.1
 	github.com/gorilla/websocket v1.5.3
@@ -19,15 +19,15 @@ require (
 	github.com/spf13/cobra v1.10.2
 	github.com/stretchr/testify v1.11.1
 	github.com/vektah/gqlparser/v2 v2.5.34
-	golang.org/x/text v0.38.0
+	golang.org/x/text v0.39.0
 	gopkg.in/yaml.v2 v2.4.0
 	gopkg.in/yaml.v3 v3.0.1
 )
 
 require (
 	filippo.io/edwards25519 v1.2.0 // indirect
 	github.com/agnivade/levenshtein v1.2.1 // indirect
-	github.com/coder/websocket v1.8.14 // indirect
+	github.com/coder/websocket v1.8.15 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/go-viper/mapstructure/v2 v2.5.0 // indirect
 	github.com/goccy/go-yaml v1.19.2 // indirect
@@ -42,9 +42,9 @@ require (
 	github.com/spf13/pflag v1.0.10 // indirect
 	github.com/stretchr/objx v0.5.3 // indirect
 	github.com/urfave/cli/v3 v3.10.0 // indirect
-	golang.org/x/crypto v0.50.0 // indirect
+	golang.org/x/crypto v0.53.0 // indirect
 	golang.org/x/mod v0.37.0 // indirect
 	golang.org/x/sync v0.21.0 // indirect
 	golang.org/x/sys v0.46.0 // indirect
-	golang.org/x/tools v0.46.0 // indirect
+	golang.org/x/tools v0.47.0 // indirect
 )

go.sum

@@ -18,8 +18,8 @@ github.com/agnivade/levenshtein v1.2.1 h1:EHBY3UOn1gwdy/VbFwgo4cxecRznFk7fKWN1KO
 github.com/agnivade/levenshtein v1.2.1/go.mod h1:QVVI16kDrtSuwcpd0p1+xMC6Z/VfhtCyDIjcwga4/DU=
 github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0 h1:jfIu9sQUG6Ig+0+Ap1h4unLjW6YQJpKZVmUzxsD4E/Q=
 github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0/go.mod h1:t2tdKJDJF9BV14lnkjHmOQgcvEKgtqs5a1N3LNdJhGE=
-github.com/coder/websocket v1.8.14 h1:9L0p0iKiNOibykf283eHkKUHHrpG7f65OE3BhhO7v9g=
-github.com/coder/websocket v1.8.14/go.mod h1:NX3SzP+inril6yawo5CQXx8+fk145lPDC6pumgx0mVg=
+github.com/coder/websocket v1.8.15 h1:6B2JPeOGlpff2Uz6vOEH1Vzpi0iUz20A+lPVhPHtNUA=
+github.com/coder/websocket v1.8.15/go.mod h1:NX3SzP+inril6yawo5CQXx8+fk145lPDC6pumgx0mVg=
 github.com/cpuguy83/go-md2man/v2 v2.0.6/go.mod h1:oOW0eioCTA6cOiMLiUPZOpcVxMig6NIQQ7OS05n1F4g=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -31,8 +31,8 @@ github.com/dgryski/trifles v0.0.0-20230903005119-f50d829f2e54/go.mod h1:if7Fbed8
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
 github.com/fsnotify/fsnotify v1.5.1/go.mod h1:T3375wBYaZdLLcVNkcVbzGHY7f1l/uK5T5Ai1i3InKU=
-github.com/go-sql-driver/mysql v1.9.3 h1:U/N249h2WzJ3Ukj8SowVFjdtZKfu9vlLZxjPXV1aweo=
-github.com/go-sql-driver/mysql v1.9.3/go.mod h1:qn46aNg1333BRMNU69Lq93t8du/dwxI64Gl8i5p1WMU=
+github.com/go-sql-driver/mysql v1.10.0 h1:Q+1LV8DkHJvSYAdR83XzuhDaTykuDx0l6fkXxoWCWfw=
+github.com/go-sql-driver/mysql v1.10.0/go.mod h1:M+cqaI7+xxXGG9swrdeUIoPG3Y3KCkF0pZej+SK+nWk=
 github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0/go.mod h1:fyg7847qk6SyHyPtNmDHnmrv/HOrqktSC+C9fM+CJOE=
 github.com/go-viper/mapstructure/v2 v2.5.0 h1:vM5IJoUAy3d7zRSVtIwQgBj7BiWtMPfmPEgAXnvj1Ro=
 github.com/go-viper/mapstructure/v2 v2.5.0/go.mod h1:oJDH3BJKyqBA2TXFhDsKDGDTlndYOZ6rGS0BRZIxGhM=
@@ -130,8 +130,8 @@ go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/crypto v0.50.0 h1:zO47/JPrL6vsNkINmLoo/PH1gcxpls50DNogFvB5ZGI=
-golang.org/x/crypto v0.50.0/go.mod h1:3muZ7vA7PBCE6xgPX7nkzzjiUq87kRItoJQM1Yo8S+Q=
+golang.org/x/crypto v0.53.0 h1:QZ4Muo8THX6CizN2vPPd5fBGHyogrdK9fG4wLPFUsto=
+golang.org/x/crypto v0.53.0/go.mod h1:DNLU434OwVakk9PzuwV8w62mAJpRJL3vsgcfp4Qnsio=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.37.0 h1:vF1DjpVEshcIqoEaauuHebaLk1O1forxjxBaVn884JQ=
 golang.org/x/mod v0.37.0/go.mod h1:m8S8VeM9r4dzDwjrKO0a1sZP3YjeMamRRlD+fmR2Q/0=
@@ -168,13 +168,13 @@ golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9sn
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.38.0 h1:sXmwo9DwP3OK9EZ7PqAdaooSGozfl/3a6/xJcbzPRhE=
-golang.org/x/text v0.38.0/go.mod h1:YXZt3QhHUKYT53r2lLKFIVi6Ao1jdzrTR/KQ09qyxF4=
+golang.org/x/text v0.39.0 h1:UbZz4pLOvn600D6Oh6GGEI6VAmndrEBLv8/6BEXzyus=
+golang.org/x/text v0.39.0/go.mod h1:3UwRclnC2g0TU9x8PZiyfOajCd1zaUNHF9cvqcQZ+ZM=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20201224043029-2b0845dc783e/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
-golang.org/x/tools v0.46.0 h1:7jTurBkPZu4moS/Uy4OQT1M+QBlsj3wejyZwsT8Z7rk=
-golang.org/x/tools v0.46.0/go.mod h1:FrD85F8l+NWL+9XWBSyVSHO6Ne4jutsfIFba7AWQ5Ys=
+golang.org/x/tools v0.47.0 h1:7Kn5x/d1svx/PzryTsqeoZN4TZwqeH5pGWjefhLi/1Q=
+golang.org/x/tools v0.47.0/go.mod h1:dFHnyTvFWY212G+h7ZY4Vsp/K3U4/7W9TyVaAul8uCA=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

internal/application/bootstrap/servers.go

@@ -21,6 +21,7 @@ import (
 	"github.com/gorilla/mux"
 	"github.com/sirupsen/logrus"
 
+	"sql-graph-visualizer/internal/application/ports"
 	graphqlserver "sql-graph-visualizer/internal/application/services/graphql"
 	"sql-graph-visualizer/internal/application/services/performance"
 	"sql-graph-visualizer/internal/domain/aggregates/graph"
@@ -179,6 +180,7 @@ func (r *Resources) startAPIServer() (*http.Server, error) {
 			r.PerformanceServices.GraphMapper,
 			r.PerformanceServices.RealtimeMonitor,
 			r.PerformanceServices.PSAdapter,
+			r.Neo4jRepo,
 		)
 		performanceHandlers.RegisterRoutes(router)
 		logrus.Info("Performance API routes registered")
@@ -361,10 +363,17 @@ func initPerformanceServices(cfg *models.Config, db *sql.DB) *PerformanceService
 	benchmarkConfig := createBenchmarkConfig(cfg)
 	// The source/graph repositories are intentionally nil here: the current
 	// benchmark execution path runs sysbench, which connects to the database
-	// directly via the configured DatabaseURL. Repositories will be wired in when
-	// benchmark-result persistence is added.
+
+	// directly via the configured DatabaseURL.
 	benchmarkService := performance.NewBenchmarkService(nil, nil, nil, performanceAnalyzer, logger, benchmarkConfig)
-	registerBenchmarkTools(benchmarkService, cfg, logger)
+	registerBenchmarkTools(benchmarkService, cfg, db, logger)
+
+	if store, err := performance.NewFileBenchmarkResultStore(logger, benchmarkResultsDir(cfg)); err != nil {
+		logrus.Warnf("Benchmark result persistence unavailable, falling back to in-memory results only: %v", err)
+	} else {
+		benchmarkService.SetResultStore(store)
+	}
+
 
 	if cfg.Performance.Realtime != nil && cfg.Performance.Realtime.Enabled {
 		ctx := context.Background()
@@ -385,50 +394,70 @@ func initPerformanceServices(cfg *models.Config, db *sql.DB) *PerformanceService
 }
 
 func createGraphMapperConfig(cfg *models.Config) *performance.GraphPerformanceMapperConfig {
-	config := &performance.GraphPerformanceMapperConfig{}
+	// Start from sane defaults so an invalid or empty duration in the user
+	// configuration falls back to a working value instead of silently
+	// zeroing the interval (which would otherwise busy-loop or never update).
+	config := performance.DefaultGraphPerformanceMapperConfig()
 	if cfg.Performance.Visualization != nil {
-		updateInterval, _ := time.ParseDuration(cfg.Performance.Visualization.UpdateInterval)
-		historyRetention, _ := time.ParseDuration(cfg.Performance.Visualization.HistoryRetention)
-		config.UpdateInterval = updateInterval
-		config.HistoryRetention = historyRetention
-		config.MaxConcurrentUpdates = cfg.Performance.Visualization.MaxConcurrentUpdates
-		if cfg.Performance.Visualization.EdgeThickness != nil {
+		v := cfg.Performance.Visualization
+		if d, err := time.ParseDuration(v.UpdateInterval); err == nil && d > 0 {
+			config.UpdateInterval = d
+		}
+		if d, err := time.ParseDuration(v.HistoryRetention); err == nil && d > 0 {
+			config.HistoryRetention = d
+		}
+		if v.MaxConcurrentUpdates > 0 {
+			config.MaxConcurrentUpdates = v.MaxConcurrentUpdates
+		}
+		if v.EdgeThickness != nil {
 			config.EdgeThickness = performance.EdgeThicknessConfig{
-				Metric:       cfg.Performance.Visualization.EdgeThickness.Metric,
-				Scale:        cfg.Performance.Visualization.EdgeThickness.Scale,
-				MinThickness: cfg.Performance.Visualization.EdgeThickness.MinThickness,
-				MaxThickness: cfg.Performance.Visualization.EdgeThickness.MaxThickness,
-				Multiplier:   cfg.Performance.Visualization.EdgeThickness.Multiplier,
+				Metric:       v.EdgeThickness.Metric,
+				Scale:        v.EdgeThickness.Scale,
+				MinThickness: v.EdgeThickness.MinThickness,
+				MaxThickness: v.EdgeThickness.MaxThickness,
+				Multiplier:   v.EdgeThickness.Multiplier,
 			}
 		}
 	}
 	return config
 }
 
 func createRealtimeConfig(cfg *models.Config) *performance.RealtimeMonitorConfig {
-	config := &performance.RealtimeMonitorConfig{}
+	// Start from sane defaults; only override fields the user actually set so
+	// an invalid/empty duration doesn't silently zero the interval.
+	config := performance.DefaultRealtimeMonitorConfig()
 	if cfg.Performance.Realtime != nil {
-		updateInterval, _ := time.ParseDuration(cfg.Performance.Realtime.UpdateInterval)
-		heartbeatInterval, _ := time.ParseDuration(cfg.Performance.Realtime.HeartbeatInterval)
-		writeTimeout, _ := time.ParseDuration(cfg.Performance.Realtime.WriteTimeout)
-		readTimeout, _ := time.ParseDuration(cfg.Performance.Realtime.ReadTimeout)
-		pingTimeout, _ := time.ParseDuration(cfg.Performance.Realtime.PingTimeout)
-		config.DataUpdateInterval = updateInterval
-		config.HeartbeatInterval = heartbeatInterval
-		config.MaxConnections = cfg.Performance.Realtime.MaxConnections
-		config.WriteTimeout = writeTimeout
-		config.ReadTimeout = readTimeout
-		config.PingTimeout = pingTimeout
-		config.MaxMessageSize = cfg.Performance.Realtime.MaxMessageSize
-		config.CompressionEnabled = cfg.Performance.Realtime.CompressionEnabled
-		if cfg.Performance.Realtime.Alerts != nil {
+		r := cfg.Performance.Realtime
+		if d, err := time.ParseDuration(r.UpdateInterval); err == nil && d > 0 {
+			config.DataUpdateInterval = d
+		}
+		if d, err := time.ParseDuration(r.HeartbeatInterval); err == nil && d > 0 {
+			config.HeartbeatInterval = d
+		}
+		if d, err := time.ParseDuration(r.WriteTimeout); err == nil && d > 0 {
+			config.WriteTimeout = d
+		}
+		if d, err := time.ParseDuration(r.ReadTimeout); err == nil && d > 0 {
+			config.ReadTimeout = d
+		}
+		if d, err := time.ParseDuration(r.PingTimeout); err == nil && d > 0 {
+			config.PingTimeout = d
+		}
+		if r.MaxConnections > 0 {
+			config.MaxConnections = r.MaxConnections
+		}
+		if r.MaxMessageSize > 0 {
+			config.MaxMessageSize = r.MaxMessageSize
+		}
+		config.CompressionEnabled = r.CompressionEnabled
+		if r.Alerts != nil {
 			config.AlertThresholds = performance.AlertThresholds{
-				HighLatency:        cfg.Performance.Realtime.Alerts.HighLatency,
-				HighErrorRate:      cfg.Performance.Realtime.Alerts.HighErrorRate,
-				HighCPUUsage:       cfg.Performance.Realtime.Alerts.HighCPUUsage,
-				HighMemoryUsage:    cfg.Performance.Realtime.Alerts.HighMemoryUsage,
-				SlowQueryThreshold: cfg.Performance.Realtime.Alerts.SlowQueryThreshold,
-				DeadlockThreshold:  cfg.Performance.Realtime.Alerts.DeadlockThreshold,
+				HighLatency:        r.Alerts.HighLatency,
+				HighErrorRate:      r.Alerts.HighErrorRate,
+				HighCPUUsage:       r.Alerts.HighCPUUsage,
+				HighMemoryUsage:    r.Alerts.HighMemoryUsage,
+				SlowQueryThreshold: r.Alerts.SlowQueryThreshold,
+				DeadlockThreshold:  r.Alerts.DeadlockThreshold,
 			}
 		}
 	}
@@ -489,10 +518,11 @@ func createBenchmarkConfig(cfg *models.Config) *performance.BenchmarkServiceConf
 	return config
 }
 
-// registerBenchmarkTools wires the available benchmark tools (currently
-// sysbench) into the benchmark service. Unavailable tools are logged and
-// skipped so the application keeps running without benchmarking support.
-func registerBenchmarkTools(svc *performance.BenchmarkService, cfg *models.Config, logger *logrus.Logger) {
+// registerBenchmarkTools wires the available benchmark tools (sysbench and,
+// when configured, custom query sets) into the benchmark service.
+// Unavailable tools are logged and skipped so the application keeps running
+// without benchmarking support.
+func registerBenchmarkTools(svc *performance.BenchmarkService, cfg *models.Config, db *sql.DB, logger *logrus.Logger) {
 	if b := cfg.Performance.Benchmarks; b != nil && !b.Enabled {
 		logrus.Info("Benchmarking disabled in configuration; skipping benchmark tool registration")
 		return
@@ -501,9 +531,66 @@ func registerBenchmarkTools(svc *performance.BenchmarkService, cfg *models.Confi
 	sysbenchAdapter := performance.NewSysbenchAdapter(logger, createSysbenchConfig(cfg))
 	if err := svc.RegisterBenchmarkTool("sysbench", sysbenchAdapter); err != nil {
 		logrus.Warnf("Sysbench benchmark tool unavailable; sysbench benchmarks disabled: %v", err)
+	} else {
+		logrus.Info("Registered sysbench benchmark tool")
+	}
+
+	querySets := createCustomQuerySets(cfg)
+	if len(querySets) == 0 {
+		return
+	}
+	customAdapter := performance.NewCustomQueryAdapter(logger, db, querySets)
+	if err := svc.RegisterBenchmarkTool("custom", customAdapter); err != nil {
+		logrus.Warnf("Custom query benchmark tool unavailable: %v", err)
 		return
 	}
-	logrus.Info("Registered sysbench benchmark tool")
+	logrus.Infof("Registered custom query benchmark tool with %d query set(s)", len(querySets))
+}
+
+// createCustomQuerySets converts the user-configured custom query benchmark
+// sets into the ports representation consumed by CustomQueryAdapter.
+func createCustomQuerySets(cfg *models.Config) map[string]ports.CustomBenchmarkConfig {
+	result := make(map[string]ports.CustomBenchmarkConfig)
+	b := cfg.Performance.Benchmarks
+	if b == nil {
+		return result
+	}
+
+	for _, set := range b.CustomQueries {
+		if set.Name == "" || len(set.Queries) == 0 {
+			continue
+		}
+
+		duration, _ := time.ParseDuration(set.Duration)
+
+		queries := make([]ports.CustomQueryDefinition, 0, len(set.Queries))
+		for _, q := range set.Queries {
+			if q.Query == "" {
+				continue
+			}
+			expectedLatency, _ := time.ParseDuration(q.ExpectedLatency)
+			queries = append(queries, ports.CustomQueryDefinition{
+				Query:           q.Query,
+				Weight:          q.Weight,
+				Parameters:      q.Parameters,
+				Description:     q.Description,
+				ExpectedLatency: expectedLatency,
+				TargetQPS:       q.TargetQPS,
+			})
+		}
+		if len(queries) == 0 {
+			continue
+		}
+
+		result[set.Name] = ports.CustomBenchmarkConfig{
+			Name:        set.Name,
+			Description: set.Description,
+			Duration:    duration,
+			Threads:     set.Threads,
+			Queries:     queries,
+		}
+	}
+	return result
 }
 
 // createSysbenchConfig maps user configuration onto the sysbench adapter config,
@@ -523,6 +610,15 @@ func createSysbenchConfig(cfg *models.Config) *performance.SysbenchConfig {
 	return sbConfig
 }
 
+// benchmarkResultsDir returns the configured directory for persisted
+// benchmark results, falling back to a sane default when unset.
+func benchmarkResultsDir(cfg *models.Config) string {
+	if b := cfg.Performance.Benchmarks; b != nil && b.ResultsDir != "" {
+		return b.ResultsDir
+	}
+	return "data/performance/benchmarks"
+}
+
 // benchmarkDatabaseURL builds a sysbench-compatible database URL and driver type
 // from the active source database configuration.
 func benchmarkDatabaseURL(cfg *models.Config) (string, string) {

internal/application/ports/benchmark_result_store_port.go

@@ -0,0 +1,39 @@
+// Package ports defines interfaces for application layer dependencies.
+package ports
+
+import (
+	"context"
+	"time"
+)
+
+// BenchmarkResultStorePort defines persistence for historical benchmark
+// results, allowing trend analysis and regression detection to survive
+// process restarts.
+type BenchmarkResultStorePort interface {
+	// Save persists a completed (or failed/cancelled) benchmark result.
+	Save(ctx context.Context, result *BenchmarkResult) error
+
+	// Get retrieves a single stored result by its execution ID.
+	Get(ctx context.Context, id string) (*BenchmarkResult, error)
+
+	// List returns stored results matching the given filter, ordered by
+	// start time ascending.
+	List(ctx context.Context, filter BenchmarkResultFilter) ([]*BenchmarkResult, error)
+
+	// DeleteOlderThan removes stored results whose start time is before the
+	// given cutoff. It returns the number of deleted results.
+	DeleteOlderThan(ctx context.Context, cutoff time.Time) (int, error)
+}
+
+// BenchmarkResultFilter narrows down which stored benchmark results to
+// return from List. Zero-valued fields are treated as "no filter" for that
+// dimension.
+type BenchmarkResultFilter struct {
+	ToolName string
+	TestType string
+	Since    time.Time
+	Until    time.Time
+	// Limit caps the number of results returned (most recent first). Zero
+	// or negative means no limit.
+	Limit int
+}