WSL Logging: Settings and Their Purpose¶
The WSL 2 global configuration file .wslconfig doesn’t clearly divide settings into sections. All but two belong to the [wsl2] section. I've grouped seven parameters that are related to logging and will go through them in this post.
I mainly use these settings when testing kernel parameters or verifying configuration changes. It’s best to disable logging during normal operation to avoid unnecessary overhead.
debugConsole¶
Opens a separate window with real-time dmesg output.
[wsl2]
# Shows a debug console with real-time dmesg output during the entire WSL instance runtime
# Dependencies:
# - Ignored if debugConsoleLogFile is set
# Default: false
# Values:
# - true
# - false
debugConsole=false
Once the debug console is opened, it displays logs from all running instances. After the instances stop, the window doesn’t close automatically, needs to close it manually.
earlyBootLogging¶
Enables logging during the early boot stages.
[wsl2]
# Enables logging from the early boot stages
# Dependencies:
# - Requires debugConsole=true or debugConsoleLogFile is set
# Default: false
# Values:
# - true
# - false
earlyBootLogging=false
Disabled by default.
debugConsoleLogFile¶
Specifies the path to a file where logs will be written.
[wsl2]
# Absolute path to debug console log file
# Dependencies: None
# Default: Not set
# Example: debugConsoleLogFile=C:\\Path\\To\\debug.log
# debugConsoleLogFile=
By default, this parameter isn’t configured, meaning logs aren’t written to a separate file. If a log file is specified and debugConsole=true won’t open the console window.
maxCrashDumpCount¶
Defines how many crash dumps are retained.
[wsl2]
# Maximum number of crash dumps to retain
# Dependencies: None
# Default: 10
# Values:
# - -1: Disable crash dump collection
# - 0: Behavior undocumented
# - Positive integer: Maximum number of dumps to keep
maxCrashDumpCount=10
The default value is 10, but can set a custom limit or disable dump creation by specifying -1.
Crash dumps can take up a significant amount of disk space, so I recommend checking the folder specified by the crashDumpFolder parameter and deleting unnecessary files. I usually disable dump creation to avoid cluttering the disk.
crashDumpFolder¶
Specifies the directory where crash dumps are stored.
[wsl2]
# Absolute path to crash dumps folder
# Dependencies:
# - Requires wsl2.MaxCrashDumpCount > 0
# Default: C:\Users\<UserName>\AppData\Local\Temp\wsl-crashes
# Example: crashDumpFolder=C:\\Path\\To\\wsl-crashes
# crashDumpFolder=
By default:
Where <UserName> is the Windows user name.
telemetry¶
Telemetry collection is enabled by default in WSL 2.
# Enables telemetry collection
# Dependencies: None
# Default: true
# Values:
# - true
# - false
telemetry=true
To view what data is being collected by enabling Turn on Diagnostic Data Viewer: Windows Settings → Privacy & Security → Diagnostic & feedback → View diagnostic data, and installing the Diagnostic Data Viewer app from the Microsoft Store.
As with crash dumps, I disable this setting to reduce the amount of data stored and transmitted.
hardwarePerformanceCounters¶
Enables hardware performance counters inside WSL instances.
[wsl2]
# Makes hardware performance counters available in WSL instances
# Dependencies:
# - Supported only on AMD64/x64
# - Not available on ARM64
# Default: true on AMD64, false on ARM64
# Values:
# - true
# - false
hardwarePerformanceCounters=true
By default, this is enabled on AMD64/x64 systems and disabled on ARM64. When enabled, WSL instances can access performance counters for profiling or performance monitoring.