Xjyuk

So, the make is Crucial MX500 2.5-INCH SSD 250GB, I bought it a half year ago and so far it works flawlessly, fine quality piece of hardware I must say.

My laptop is w/o battery and I guess sometimes I might just unplug the machine from the power network (w/o properly shutting it down, even though it takes 1 second..) and move it somewhere else.

OS - Ubuntu 18.04 LTS, I saw the above message (see title) and was wondering why is that?

On the next start of disks utility the message was gone, I read that it means that the sector was "re-allocated" or something?

Is there something wrong with the disk, is it because I am not paying too much attention on how I am using it and stuff?

P.S. How many sectors are there anyway, and is this something that would affect system performance or anything else?

SSDs are based on blocks rather than sectors, which are associated with hard disk drives. You indicated that the message was from the Gnome Disk Utility, so that likely responds to the general error with an old message.

One bad block (or sector) doesn't mean too much. Any drive can get a failure in one or a few locations. When it happens, the drive controller tries to relocate the contents to another block (or sector). It will spend some time retrying it and moving content. That will momentarily affect performance, but you may not notice it because it will be similar to the drive just being busy.

Eventually, the drive will run out of spares and become unusable. The issue isn't so much the number of bad blocks in relation to the total number of blocks, it's the number in relation to the number of spares. Drives are provisioned with adequate spares for expected failure rates over the planned life of the drive.

In normal use, there will be an occasional random failure. The problem is when there is a recurring pattern with new bad blocks. That indicates the drive is in the process of failing an unnatural death.

So seeing that message is good from the perspective that something is keeping track of it and alerting you, so you will be aware of a problem if you start seeing the message on more than rare occasions.

Ramhound's comment about hard shutdown is a different issue. If you just pull the plug instead of shutting down gracefully, the drive may be left with corruption because write operations may not have been completed. That won't be physical damage, but you're likely to get a message either that a bad sector was detected or that there could potentially be a problem.

The operating system is aware of when the system was not shut down properly and knows to check the drive for corruption just in case there was any. Depending on the nature of the corruption, you might have a file that can't be recovered, or even a system problem if a critical file was left unusable. But recovery from that typically doesn't use up spare blocks.

Even though you aren't likely to cause physical damage with a hard shutdown, it will cause problems that are a pain in the butt. Best case, you will have a very long boot time while it checks for potential corruption. Worst case, you will lose files or need to spend time recovering system files to get operational again. So don't just pull the plug.

Beyond theory, the best answer to your question, “Is there something wrong with the disk,” is we can’t tell you.

However, the best way to find out is to use the manufacturer provided tool called Storage Executive to find out the status and health of your drive. Additionally, you can perform maintenance tasks such as upgrading the firmware.

Unfortunately, this appears to only be available on Windows.