diskmon.exe

DiskMon Disk I/O Monitoring Utility

CPU Usage

N/A

Memory

N/A

Location

N/A

Publisher

N/A

Data Formats

DiskMon outputs line-based text logs with timestamps, process IDs, file names, operation type, and latency metrics; enable log rotation to manage size.

Best Practices

Run DiskMon with a defined duration, export logs for later analysis, and correlate events with proc events to avoid overwhelming noise.

Usage Scenarios

In performance tuning, DiskMon is used to map I/O hotspots, verify improvements after storage changes, and show which apps trigger heavy disk access.

What is diskmon.exe?

DiskMon.exe is a Sysinternals utility that captures real-time disk input/output events on Windows, logging reads, writes, timestamps, process IDs, and file paths. It provides granular visibility into storage activity, helping IT admins pinpoint bottlenecks, verify application behavior, and validate storage subsystem performance under load.

DiskMon hooks into I/O paths to emit event records that include IRP major/minor codes, process context, and I/O duration. It outputs data to the console or a log file, enabling targeted analysis of which processes stress disks and how storage latency responds under load.

Is diskmon-exe Safe?

DiskMon.exe is a legitimate Sysinternals utility distributed by Microsoft. When downloaded from the official Sysinternals site or trusted IT bundles, it runs in user or admin mode without altering system files beyond its own binary. Used responsibly, it is a safe diagnostic tool that improves visibility into disk I/O and can be removed cleanly when not needed.

Is diskmon-exe a Virus?

DiskMon.exe can be misrepresented by malware if downloaded from untrusted sources or renamed to resemble the genuine tool. If the binary appears in an unexpected folder, lacks a valid digital signature, or differs from the official release, treat it as suspicious. Always verify publisher, source, and file integrity before running.

How to Verify Legitimacy

Check File Location: Verify diskmon.exe resides under a legitimate Sysinternals directory such as C:\Sysinternals\DiskMon or a trusted software bundle.
Verify Digital Signature: Open file properties and confirm a valid signature from Microsoft Corporation / Sysinternals.
Check File Hash: Compute SHA-256 of the diskmon.exe and compare against the official release manifest or trusted download source.
Scan for Malware: Run a malware scan with Windows Defender or your endpoint AV to ensure no related threats exist.

Red Flags: If diskmon.exe is located outside the Sysinternals directory, is unsigned, or shows unexpected digital signatures, treat as suspicious and isolate it from the system until verified.

Why is it Running?

Reasons it's running:

Real-time disk I/O monitoring: DiskMon records live reads and writes, latency, and queue depth so admins can see which processes stress storage in real time.
Diagnostics for storage bottlenecks: By correlating I/O events with process names and file paths, DiskMon helps pinpoint bottlenecks on specific volumes or subsystems.
Post-change validation: Run DiskMon after storage or driver changes to verify that I/O behavior improves or remains stable under load.
IT monitoring and audits: DiskMon is commonly used in Sysinternals-driven troubleshooting workflows for performance audits and incident response.
Part of Sysinternals suite: As a member of the Sysinternals toolkit, DiskMon is used alongside ProcMon, Handle, and other tools for comprehensive system analysis.

Can I Disable or Remove It?

Common Problems

Common Causes & Solutions

: Limit logging to a timeframe, use sampling intervals, and ensure the output log file is rotated to avoid large files that increase CPU load.
: Ensure DiskMon is run with administrative privileges and that disk I/O activity is actually occurring on the targeted drives.
: Run from an elevated command prompt, verify the executable integrity, and check for conflicting Sysinternals tools with the same executable name.
: Check disk subsystem drivers and storage controllers for compatibility and capture settings; consider updating to the latest Sysinternals release.
: Review startup tasks and services to remove auto-run entries; re-install DiskMon if used within a scripted diagnostic workflow.
: Submit the binary for white-listing with your AV vendor, verify signature, and ensure the file comes from a trusted Sysinternals source.

Frequently Asked Questions

What is diskmon.exe and what does it do?

DiskMon.exe is a Sysinternals disk I/O monitoring tool that logs real-time read/write activity, latency, and process context. It helps diagnose storage issues by showing which processes access which files and when.

Is diskmon.exe safe to run on my Windows machine?

Yes, if downloaded from the official Sysinternals site or trusted bundles. It does not harm the system when used as intended, and it can be removed easily when you no longer need its monitoring capabilities.

Can I disable or remove diskmon.exe after installation?

Yes. You can close the tool, remove startup entries, and delete the diskmon directory. Ensure you do not rely on it for ongoing monitoring if you remove it.

Where is diskmon.exe located by default?

Common locations include C:\Sysinternals\DiskMon\diskmon.exe or within a Sysinternals/Tools folder depending on how you installed the suite.

Why might antivirus flag diskmon.exe as suspicious?

Because it monitors low-level I/O, some AV heuristics may flag it. Ensure the signature is valid and the source is trusted; submit for whitelisting if needed.

How do I uninstall DiskMon and related Sysinternals tools?

Remove the DiskMon executable and any Sysinternals tools from the installation directory, then clean up startup entries and registry keys if you added them manually.