pt-mongodb-summary: major improvements and new sections (PT-2368)

src/go/mongolib/proto/cmdlineopts.go

@@ -25,24 +25,39 @@ type Sharding struct {
 	ClusterRole string `bson:"clusterRole"`
 }
 
+type CloStorageWT struct {
+	EngineConfig struct {
+		CacheSizeGB float64 `bson:"cacheSizeGB"`
+	} `bson:"engineConfig"`
+}
+
 type CloStorage struct {
-	DbPath string `bson:"dbPath"`
-	Engine string `bson:"engine"`
+	DbPath     string       `bson:"dbPath"`
+	Engine     string       `bson:"engine"`
+	WiredTiger CloStorageWT `bson:"wiredTiger"`
 }
 
 type CloSystemLog struct {
 	Destination string `bson:"destination"`
 	Path        string `bson:"path"`
+	LogAppend   bool   `bson:"logAppend"`
+}
+
+type OperationProfiling struct {
+	Mode              string `bson:"mode"`
+	SlowOpThresholdMs int64  `bson:"slowOpThresholdMs"`
 }
 
 type Parsed struct {
-	Sharding          Sharding          `bson:"sharding"`
-	Storage           CloStorage        `bson:"storage"`
-	SystemLog         CloSystemLog      `bson:"systemLog"`
-	Net               Net               `bson:"net"`
-	ProcessManagement ProcessManagement `bson:"processManagement"`
-	Replication       Replication       `bson:"replication"`
-	Security          Security          `bson:"security"`
+	Config              string              `bson:"config"`
+	Sharding            Sharding            `bson:"sharding"`
+	Storage             CloStorage          `bson:"storage"`
+	SystemLog           CloSystemLog        `bson:"systemLog"`
+	Net                 Net                 `bson:"net"`
+	ProcessManagement   ProcessManagement   `bson:"processManagement"`
+	Replication         Replication         `bson:"replication"`
+	Security            Security            `bson:"security"`
+	OperationProfiling  OperationProfiling  `bson:"operationProfiling"`
 }
 
 // Security is a struct to hold security related configs

src/go/mongolib/proto/server_status.go

@@ -40,6 +40,23 @@ type ServerStatus struct {
 	ShardCursorType    map[string]interface{} `bson:"shardCursorType"`
 	StorageEngine      StorageEngine          `bson:"storageEngine"`
 	WiredTiger         *WiredTiger            `bson:"wiredTiger"`
+	Tcmalloc           *TcmallocStats         `bson:"tcmalloc"`
+}
+
+type TcmallocStats struct {
+	Generic struct {
+		CurrentAllocatedBytes int64 `bson:"current_allocated_bytes"`
+		HeapSize              int64 `bson:"heap_size"`
+	} `bson:"generic"`
+	Tcmalloc struct {
+		PageheapFreeBytes            int64 `bson:"pageheap_free_bytes"`
+		PageheapUnmappedBytes        int64 `bson:"pageheap_unmapped_bytes"`
+		MaxTotalThreadCacheBytes     int64 `bson:"max_total_thread_cache_bytes"`
+		CurrentTotalThreadCacheBytes int64 `bson:"current_total_thread_cache_bytes"`
+		CentralCacheFreeBytes        int64 `bson:"central_cache_free_bytes"`
+		TransferCacheFreeBytes       int64 `bson:"transfer_cache_free_bytes"`
+		ThreadCacheFreeBytes         int64 `bson:"thread_cache_free_bytes"`
+	} `bson:"tcmalloc"`
 }
 
 type StorageEngine struct {
@@ -67,9 +84,13 @@ type ConcurrentTransStats struct {
 
 // CacheStats stores cache statistics for WiredTiger.
 type CacheStats struct {
-	TrackedDirtyBytes  int64 `bson:"tracked dirty bytes in the cache"`
-	CurrentCachedBytes int64 `bson:"bytes currently in the cache"`
-	MaxBytesConfigured int64 `bson:"maximum bytes configured"`
+	TrackedDirtyBytes      int64 `bson:"tracked dirty bytes in the cache"`
+	CurrentCachedBytes     int64 `bson:"bytes currently in the cache"`
+	MaxBytesConfigured     int64 `bson:"maximum bytes configured"`
+	PagesEvictedUnmodified int64 `bson:"unmodified pages evicted"`
+	PagesEvictedModified   int64 `bson:"modified pages evicted"`
+	PagesReadIntoCache     int64 `bson:"pages read into cache"`
+	PagesWrittenFromCache  int64 `bson:"pages written from cache"`
 }
 
 // TransactionStats stores transaction checkpoints in WiredTiger.

src/go/pt-mongodb-summary/CLAUDE.md

@@ -0,0 +1,76 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Commands
+
+All make commands run from `/src/go/` (the Go module root), not the tool directory itself.
+
+**Build:**
+```bash
+make build                # Build for current platform → ../../bin/pt-mongodb-summary
+make linux-amd64          # Cross-compile for Linux x86-64
+make darwin-arm64         # Cross-compile for macOS Apple Silicon
+VERSION=3.7.1 make linux-amd64  # Build with version embedded via LDFLAGS
+```
+
+**Test:**
+```bash
+make test                 # Runs ./runtests.sh (requires Docker for MongoDB containers)
+make env-up               # Start MongoDB test containers (standalone + sharded cluster)
+make env-down             # Stop test containers
+go test -v ./...          # Run tests directly (from tool directory)
+go test -v -run TestName ./...  # Run a specific test
+```
+
+**Lint & Format:**
+```bash
+make style                # Check formatting with gofmt
+make vet                  # Run go vet
+make format               # Auto-format with gofumpt and gofumports
+```
+
+## Architecture
+
+`pt-mongodb-summary` connects to a MongoDB instance (standalone, replica set, or sharded cluster), collects diagnostic data via admin commands, and renders a human-readable or JSON report.
+
+### Data flow
+
+```
+main() → connect → collect → format → output
+```
+
+1. **Connect** (`getClientOptions`): Builds `*options.ClientOptions` from CLI flags or URI, handling TLS and auth.
+2. **Collect**: Each `get*` function runs MongoDB admin commands and returns a typed struct:
+   - `getHostInfo` → `hostInfo` (hostInfo, serverStatus, cmdLineOpts commands)
+   - `getMongosInfo` → `mongosInfo` (queries `config.mongos` collection)
+   - `getSecuritySettings` → `security` (auth/SSL from serverStatus + usersInfo + rolesInfo)
+   - `getOpCountersStats` → `opCounters` (samples serverStatus N times)
+   - `oplog.GetOplogInfo` → `[]proto.OplogInfo` (reads local.oplog.rs)
+   - `getClusterwideInfo` → `clusterwideInfo` (listDatabases, collStats, sh.status; mongos only)
+   - `GetBalancerStats` → `proto.BalancerStats` (parses config.changelog; mongos only)
+3. **Aggregate** into `collectedInfo` struct.
+4. **Format** (`formatResults`): Either marshal to JSON or render via Go templates in `templates/`.
+
+### Templates
+
+Each report section has a dedicated template file under `templates/`. Templates receive the full `collectedInfo` struct. Adding a new output section means adding a template file and calling it from `formatResults`.
+
+### Shared packages
+
+- `../../mongolib/proto/` — shared MongoDB data types (e.g., `Members`, `OplogInfo`, `BalancerStats`)
+- `../../mongolib/util/` — MongoDB helpers (e.g., `GetReplicasetMembers`)
+- `../../lib/config/` — config file loading
+- `../../lib/versioncheck/` — online version check against Percona's API
+- `../../internal/testutils/` — test helpers (connection setup, fixtures)
+
+### Test fixtures
+
+Sample MongoDB command responses live in `test/sample/*.json`. Tests in `main_test.go` unmarshal these fixtures to test parsing logic without a live MongoDB connection. Integration tests (via `runtests.sh`) require the Docker cluster from `make env-up`.
+
+## Key conventions
+
+- CLI parsing uses `github.com/alecthomas/kong` via `config.Setup()`. New options are added as fields with kong struct tags in `cliOptions`. Validation and side-effects (log level, version check, password prompt, positional host:port) go in `AfterApply()`. Config files (`~/.pt-mongodb-summary.conf`, `/etc/percona-toolkit/pt-mongodb-summary.conf`) are automatically supported.
+- Logging is via `github.com/sirupsen/logrus`; level is set from `--log-level` flag.
+- MongoDB connection URI takes precedence over individual host/port/auth flags.
+- The binary embeds `Version`, `Build`, `GoVersion`, and `Commit` via LDFLAGS at build time.