Reallocated Sector Count

[acidydragon]

Hello all! With my ever enduring computer issues, I've run a test on my HDD just to be curious.

 

I got the result back "Reallocated Sector Count - 1156 - Warning"

 

Is my HDD going to die, or can I generally ignore this warning?

[flibberdipper]

I don't see a need to worry. Hell, I used my old 15GB Fireball to the point it only had 50MB usable...

[Altecice]

As above dont panic if it stays the same. If it is rising each time then you want to start worrying and thinking about a new drive.

[alpenwasser]

Yes, that is something to be worried about AFAIK:

Count of reallocated sectors. When the hard drive finds a read/write/verification error, it marks that sector as "reallocated" and transfers data to a special reserved area (spare area). This process is also known as remapping, and reallocated sectors are called "remaps". The raw value normally represents a count of the bad sectors that have been found and remapped. Thus, the higher the attribute value, the more sectors the drive has had to reallocate. This allows a drive with bad sectors to continue operation; however, a drive which has had any reallocations at all is significantly more likely to fail in the near future.[3] While primarily used as a metric of the life expectancy of the drive, this number also affects performance. As the count of reallocated sectors increases, the read/write speed tends to become worse because the drive head is forced to seek to the reserved area whenever a remap is accessed. If sequential access speed is critical, the remapped sectors can be manually marked as bad blocks in the file system in order to prevent their use.

Wikipedia has a pretty thorough article on S.M.A.R.T., you can read more about what

the different test criteria in a S.M.A.R.T. check mean, specifically which ones indicate failure.

[flibberdipper]

Yes, that is something to be worried about AFAIK:

Wikipedia has a pretty thorough article on S.M.A.R.T., you can read more about what

the different test criteria in a S.M.A.R.T. check mean, specifically which ones indicate failure.

But... My Fireball...

[Vitalius]

Your drive have hundreds of millions of sectors so you should not panic if 0.00001% of them got reallocated.

 

This is a bad attitude to take.

Yes, that is something to be worried about AFAIK:

Wikipedia has a pretty thorough article on S.M.A.R.T., you can read more about what

the different test criteria in a S.M.A.R.T. check mean, specifically which ones indicate failure.

 

This.

But... My Fireball...

There are obvious exceptions. Some drives "just work forever". They are rare, but they happen. 

@acidydragon, each HDD usually gets 256-2560 spare sectors to reallocate to. You are almost half way through them. That's why your HDD is giving a warning. 

[alpenwasser]

But... My Fireball...

There are obvious exceptions. Some drives "just work forever". They are rare, but they happen.

Some people just get lucky. I have quite a few Samsung drives ranging in age from

anything between a bit more than 5 and about 8 years. The youngest ones are three

1 TB Spinpoints from 2008. All of them have something between 20k and 30k power_on

hours on them IIRC (don't have them plugged in at the moment, so can't verify, but

it is of about that magnitude), they ran in my PC pretty much 24/7 for quite a while.

Recent SMART checks gave me OK health for all of those three, while some others

have failed despite not having as many hours on them (those are a bit older though).

The point of my ramble being: Luck of the draw.

[Vitalius]

Some people just get lucky. I have quite a few Samsung drives ranging in age from

anything between a bit more than 5 and about 8 years. The youngest ones are three

1 TB Spinpoints from 2008. All of them have something between 20k and 30k power_on

hours on them IIRC (don't have them plugged in at the moment, so can't verify, but

it is of about that magnitude), they ran in my PC pretty much 24/7 for quite a while.

Recent SMART checks gave me OK health for all of those three, while some others

have failed despite not having as many hours on them (those are a bit older though).

The point of my ramble being: Luck of the draw.

Yup.

Interestingly, the FreeNAS Noob guide on their forums mentions that HDDs tend to last longer the less sleep states they use. So leaving them running rather than conserving power with them preserves their life, and no one has figured out why. 

I thought that was pretty cool.

[acidydragon]

Would this cause my computer to run slow or have any issues (I'm still replacing the drive, but I'm trying to diagnose my computer too!)

[alpenwasser]

Yup.

Interestingly, the FreeNAS Noob guide on their forums mentions that HDDs tend to last longer the less sleep states they use. So leaving them running rather than conserving power with them preserves their life, and no one has figured out why. 

I thought that was pretty cool.

That is interesting. I must say I have been positively surprised by how well my

Samsungs have held up over the years. I think (and this is just conjecture)

that running idly in a friendly environment (acceptable temperature, no excessive

vibrations and so on) might put less strain on the drive than being powered up

and down (i.e. the PC being turned off when it's not needed).

I could easily imagine power saving features impacting drive life. Mechanically

speaking, spinning up and down and parking and unparking heads puts more stress

on the mechanical assembly than just letting the spindles keep rotating when the

drive is not in use. Then there's also the question of the fluid dynamic bearings,

which certainly would prefer to just be kept rotating instead of being stopped and

started again (at least if I recall my mechanical engineering lectures correctly).

When starting an FDB up, the lubricant is not yet ideally distributed within the

bearing, which can cause undesired wear (not a lot, but if the bearing is stopped

and started frequently this effect will start to add up).

I also recall WD's problems with Intellipark on their WD Greens in Linux a while

back (last I heard that had been resolved, though I'm not sure if from the Linux

side or with a modified firmware), which could lead to a hundred or more parking/

unparking events in an hour, and could therefore reach the drive's spec limits

(300,000 events for a WD Green according to Wikipedia) unpleasently quickly.

Anyway, I'm starting to ramble again.

EDIT:

Would this cause my computer to run slow or have any issues (I'm still replacing the drive, but I'm trying to diagnose my computer too!)

As the Wiki article states, yes this is plausible. Basically every time your drive

needs to access a reallocated sector, it needs to move its head to that sector and

then go back to where it was reading from before. I think of it as heavy fragmentation.

[acidydragon]

As the Wiki article states, yes this is plausible. Basically every time your drive

needs to access a reallocated sector, it needs to move its head to that sector and

then go back to where it was reading from before. I think of it as heavy fragmentation.

 

Thanks a ton! Hopefully this fixes my issues...