Readme for health monitor (#899)

Adding readme for health monitor

cmd/health-monitor.go

@@ -167,7 +167,7 @@ func buildCliParamForMonitor() []string {
 		case hmcommon.NetworkProfiler:
 			cliParams = append(cliParams, "--no-network-profiler")
 		case hmcommon.FileCacheMon:
-			cliParams = append(cliParams, "--no-cache-monitor")
+			cliParams = append(cliParams, "--no-file-cache-monitor")
 		default:
 			log.Debug("health-monitor::buildCliParamForMonitor: Invalid health monitor option %v", v)
 		}

setup/baseConfig.yaml

@@ -128,7 +128,7 @@ health_monitor:
   # list of monitors to be disabled
   monitor-disable-list:
     - blobfuse_stats <Disable blobfuse2 stats polling>
-    - cache_monitor <Disable file cache directory monitor>
+    - file_cache_monitor <Disable file cache directory monitor>
     - cpu_profiler <Disable CPU monitoring on blobfuse2 process>
     - memory_profiler <Disable memory monitoring on blobfuse2 process>
     - network_profiler <Disable network monitoring on blobfuse2 process>

tools/health-monitor/README.md

@@ -0,0 +1,99 @@
+# Blobfuse2 Health Monitor (Preview)
+
+## About
+
+Blobfuse2 Health Monitor is a tool which will help in monitoring Blobfuse2 mounts. It supports the following types of monitors:
+
+1. **Blobfuse2 Stats Monitor:** Monitor the different statistics of blobfuse2 components like,
+    - Total bytes uploaded and downloaded via blobfuse2
+    - Events like create, delete, rename, synchronize, truncate, etc. on files or directories in the mounted directory
+    - Progress of uploads or downloads of large files to/from Azure Storage
+    - Keep track of number of calls that were made to Azure Storage for operations like create, delete, rename, chmod, etc. in the mounted directory
+    - Total number of open handles on files
+    - Number of times an open file request was served from the file cache or downloaded from the Azure Storage  
+
+2. **CPU and Memory Monitor:** Monitor the CPU and memory usage of the Blobfuse2 process associated with the mount
+
+3. **File Cache Monitor:** Monitor the file cache directory specified while mounting. This monitor does the following,
+    - Monitor the different events like create, delete, rename, chmod, etc. of files and directories in the cache
+    - Keep track of the cache consumption with respect to the cache size specified during mounting
+
+> **Note:** Health Monitor runs as a separate process where one health monitor process is associated with monitoring one blobfuse2 mounted directory.
+
+## Enable Health Monitor
+
+The different configuration options for the health monitor are,
+- `enable-monitoring: true|false`: Boolean parameter to enable health monitor. By default it is disabled
+- `stats-poll-interval-sec: <TIME IN SECONDS>`: Blobfuse2 stats polling interval (in sec). Default is 10 seconds
+- `process-monitor-interval-sec: <TIME IN SECONDS>`: CPU and memory usage polling interval (in sec). Default is 30 sec
+- `output-path: <PATH>`: Path where health monitor will generate its output file. It takes the current directory as default, if not specified. Output file name will be `monitor_<pid>.json`
+- `monitor-disable-list: <LIST OF MONITORS>`: List of monitors to be disabled. To disable a monitor, add its corresponding name in the list
+    - `blobfuse_stats` - Disable blobfuse2 stats polling
+    - `cpu_profiler` - Disable CPU monitoring on blobfuse2 process
+    - `memory_profiler` - Disable memory monitoring on blobfuse2 process
+    - `file_cache_monitor` - Disable file cache directory monitor
+
+### Sample Config
+
+Add the following section to your blobfuse2 config file. Here file cache and memory monitors are disabled.
+```yaml
+health_monitor:
+  enable-monitoring: true
+  stats-poll-interval-sec: 10
+  process-monitor-interval-sec: 30
+  output-path: outputReportsPath
+  monitor-disable-list:
+    - file_cache_monitor
+    - memory_profiler
+```
+
+## Output Reports
+
+Health monitor will store its output reports in the path specified in the `output-path` config option. If this option is not specified, it takes the current directory as default. It stores the last 100MB of monitor data in 10 different files named as `monitor_<pid>_<index>.json` where `monitor_<pid>.json`(Zeroth index) is latest and `monitor_<pid>_9.json` is the oldest output file.
+
+### Sample Output
+
+```
+{
+    "Timestamp": "t1",
+    "CPUUsage": "value in %",
+    "MemoryUsage": "value in bytes",
+    "BlobfuseStats": [
+        {
+            "componentName": "azstorage",
+            "value": {
+                "Bytes Downloaded": value in bytes,
+                "Bytes Uploaded": value in bytes,
+                "Chmod": count of chmod calls,
+                "StreamDir": count of stream dir calls
+            }
+        },
+        {
+            "componentName": "file_cache",
+            "value": {
+                "Cache Usage": "value in MB",
+                "Usage Percent": "value in %",
+                "Files Downloaded": count,
+                "Files served from cache": count
+            }
+        }
+    ],
+    "FileCache": [
+        {
+            "cacheEvent": "CREATE",
+            "path": "filePath",
+            "isDir": false,
+            "cacheSize": value in bytes,
+            "cacheConsumed": "value in %",
+            "cacheFilesCount": count of files in cache,
+            "evictedFilesCount": count of files evicted from cache,
+            "value": {
+                "FileSize": "value in bytes"
+            }
+        }
+    ]
+}
+```
+
+
+

tools/health-monitor/common/types.go

@@ -39,7 +39,7 @@ import (
 
 const (
 	BlobfuseStats   = "blobfuse_stats"
-	FileCacheMon    = "cache_monitor"
+	FileCacheMon    = "file_cache_monitor"
 	CpuProfiler     = "cpu_profiler"
 	MemoryProfiler  = "memory_profiler"
 	NetworkProfiler = "network_profiler"

tools/health-monitor/main.go

@@ -154,7 +154,7 @@ func init() {
 	flag.BoolVar(&hmcommon.NoCpuProf, "no-cpu-profiler", false, "Disable CPU monitoring on blobfuse2 process")
 	flag.BoolVar(&hmcommon.NoMemProf, "no-memory-profiler", false, "Disable memory monitoring on blobfuse2 process")
 	flag.BoolVar(&hmcommon.NoNetProf, "no-network-profiler", false, "Disable network monitoring on blobfuse2 process")
-	flag.BoolVar(&hmcommon.NoFileCacheMon, "no-cache-monitor", false, "Disable file cache directory monitor")
+	flag.BoolVar(&hmcommon.NoFileCacheMon, "no-file-cache-monitor", false, "Disable file cache directory monitor")
 
 	flag.StringVar(&hmcommon.TempCachePath, "cache-path", "", "path to local disk cache")
 	flag.Float64Var(&hmcommon.MaxCacheSize, "max-size-mb", 0, "maximum cache size allowed. Default - 0 (unlimited)")