Question:Closed 8 years ago. ?
How long will it take to zero fill 1TB (using dd dev/zero)?
I’m actually doing two 500G drive simultaneously if it matters.
Answer: It depends on many factors, including but not limited to: ?
- Disk speed (RPM)
- Disk built-in cache
- Number of platters and whether it can write to multiple platters simultaneously
- Disk interface (SATA/SCSI, etc)
- Interface controller performance
- Configuration of the drives (eg. separate channels or same channel)
Additionally, although zeroing a drive is a simple task for the CPU and RAM, there may still be an effect from: ?
- CPU performance
- Available RAM
- Speed of RAM
- Other tasks being done at the same time
- Power management settings
Assuming a fairly recent computer with middle-grade drives, on a minimal linux boot disk running JUST the zeroing operation (no gui, internet, etc) loaded entirely to RAM, it could be anywhere from 2-12 hours. ?If I had to throw a single number out, I’d say closer to 3 and a half hours, but again, there’s not enough information to get a good estimate other than actually doing it. ?
If you have more than 1GB free space, you could try mounting the drive and running dd if=/dev/zero bs=512 count=2048 of=/tmp/tempzero or some other file. ?If you know more about the optimal block size for fastest writing to your drive, you can use that for the bs value (in kilobytes) and set the count to whatever gets you the filesize you want. ?Then you can use that to get a better estimate without losing data. ?It will just create a large file that contains zeros.