Troubleshooting

Disk Tools: speed, health and a check for every drive

Test a drive’s speed, read its health, see its format with advice, and check it for damage without changing anything. Free, for any mounted drive.

By the MoreRoom team, Yando Pte. Ltd.This page as Markdown

In short

  • Disk Tools is in the sidebar, under Overview. Choose any drive mounted on your Mac: the startup disk, an external drive, a USB stick or an SD card.
  • The speed test measures how fast the drive writes and reads, plus small random accesses, then says in plain words what the drive is fast enough for.
  • Health shows SMART status, wear and temperature when the drive reports them. Details gives the format with advice. The check looks for damage without changing anything. All free.

How to test a drive’s speed with MoreRoom

  1. Open Disk Tools Click Disk Tools in the sidebar, under Overview.
  2. Choose the drive Click the drive at the top of the window. Each one shows its size and free space.
  3. Start the test Click Start Test. MoreRoom writes a temporary file, reads it back, then measures random reads and writes. You can click Stop at any time.
  4. Read the verdicts Under What this drive is good for, each use gets a check mark when the drive is fast enough, with a short reason.

Open Disk Tools

Click Disk Tools in the sidebar, under Overview. It doesn’t need a scan.

At the top, every drive mounted on your Mac is listed with its size and free space: Macintosh HD, external SSDs and hard disks, USB sticks, SD cards, disk images and network volumes. Click one to choose it; the cards below then describe that drive.

Disk Tools is free: no Pro badge, no limit.

Speed Test

Click Start Test. MoreRoom:

  1. writes a temporary file to the drive in several passes, then reads it back, with caching turned off so the result is the drive’s own speed, not your Mac’s memory;
  2. measures random 4K reads and writes (in IOPS, operations per second) — the small, scattered accesses that apps, libraries and virtual machines make;
  3. deletes the temporary file. It’s always deleted afterwards.

While it runs, two dials show the Write and Read speed in MB/s. At the end you see the random read and write figures and the size of the test file. Click Stop to end it early, or Test Again later.

Reading the verdicts

Under What this drive is good for, MoreRoom compares the results with what common uses need: 4K video editing, Photos / Lightroom libraries, AI models & simulators, Virtual machines, Time Machine backups and Archiving / cold storage.

  • A check mark and Fast enough means the drive keeps up with that use. The measured speed is shown.
  • A cross and Too slow shows what was measured and what is needed.

A drive that’s too slow for video editing can still be perfectly fine for backups or archives.

Why it needs free space

The test writes a real file to the drive, so it needs about 1.1 GB free. Below that, Start Test stays dimmed: free some space on the drive first. A drive that can’t be written to — mounted read-only, for example — can’t be tested.

Only the temporary file is written; nothing else on the drive is touched.

Health

The Health card gives an overall verdict — Good, Needs attention, Failing or Not reported — with the reasons when something is wrong. Depending on the drive, it shows:

  • SMART status: the drive’s own self-assessment (Verified, Failing or Not supported);
  • Wear, Temperature, Data written and Powered on hours, for drives that share them with macOS;
  • the Model, whether TRIM is on, and Encryption.

“Not reported” on an external drive

Many external drives don’t pass health data to macOS: USB adapters usually don’t forward SMART status, and some drives don’t share wear or temperature. MoreRoom then shows Not reported, with a short note explaining why.

It doesn’t mean the drive has a problem — only that macOS can’t see its health. For a network volume, health can only be read on the server; for a disk image, it’s that of the drive holding the image file.

Details

The Details card shows the drive’s Format (APFS, Mac OS Extended, ExFAT…), Capacity, Available space, Local snapshots, whether it’s a Time Machine backup disk, and its Device name.

Below, short advice appears when it matters, for example:

  • the drive is nearly full;
  • its format can’t store files over 4 GB, or isn’t suited to Time Machine;
  • it’s NTFS, which macOS can only read;
  • it’s an SSD that would work better as APFS;
  • it isn’t encrypted — Finder can encrypt it: Control-click the drive › Encrypt;
  • it’s case-sensitive, which some apps don’t support.

Check this disk

Click Check. MoreRoom reads the whole file system structure without changing anything, like the check Disk Utility’s First Aid runs. It can take a few minutes, and you can click Stop. The speed test and the check don’t run at the same time.

  • No damage found. Sometimes with “macOS noted minor issues it can live with”: there’s nothing to do.
  • Problems found. MoreRoom lists the first ones. It doesn’t repair anything itself: open Disk Utility, select the disk and click First Aid.
  • Couldn’t be checked. The reason is shown — for example the volume is in use, it’s a network volume, or the disk was disconnected.

Good to know

  • Disk Tools never changes your files: the speed test only writes its own temporary file and deletes it, and the check is read-only.
  • To see what fills a drive, scan it: see Scan your Mac.
  • If MoreRoom’s free space differs from Finder’s, see Why numbers differ.