Hard Disk Monitoring

I did a surface test on one of my external hard disks and the result is attached.
There is a large dark green colored area. Should I worry about this disk? I use it for backup.

No, you do not need to worry.

As you can see on the right, there are no yellow / red blocks, all sectors are working perfectly, as should.

The slightly darker color indicates that the disk drive may perform a bit slower than expected (on the "Temperature and transfer speed" page you can examine the performance graph of the drive) but alone this does not cause problems and can be normal.

You'd need to worry only if the color would be MUCH more dark (almost black) indicating much slower performance and/or if there would be yellow/red blocks displayed near (or inside) this darker green area, as for example on this image:



as it indicates that more such sectors will be not only very slow but also will be damaged/failed with time.

Thank you for the explanation. As I wrote, I use this disk for my backups and if it's a bit slow it doesn't matter to me as long as it's sufficiently healthy.