Question: What problem in using Enterprise HDD in Desktop setup?

[jayraw]

(Sorry if this issue has been answered already. Couldn't find it. If it is, please link)

Hello,

Question: What kind of problems should I expect to get into if I am using an enterprise drive in a regular desktop computer?

Target enterprise hdd: Seagate Constellation ES, HGST A7K2000 (1TB, sata)

The setup:
Currently using a 500gb HGST 7200rpm drive as main drive. (Also use Sandisk Readycache. But that's irrelevant). No RAID set up. I am using ahci (SATA ports).

Intend to use the enterprise drive as dual partitioned with an image of windows on a small partition and the rest for back ups. But I might end up using it as a main drive as well. In that case it'll only replace my current drive and everything else will remain unchanged.

So, curious if enterprise drive would behave differently in desktop? I read some stuff about error correction and timing something something.. may be that would have an effect?

I appreciate your comments.. Thanks.

 

[The_OGS]

Enterprise drives are 'better' - more heavy duty. Able to run 24/7. Cooler temps. More robust design (longer warranty).
NCQ will help speed things along (but most AHCI SATA drives use it these days).
That's about it! Enjoy...

 

[jayraw]

Enterprise drives are 'better' - more heavy duty. Able to run 24/7. Cooler temps. More robust design (longer warranty).
NCQ will help speed things along (but most AHCI SATA drives use it these days).
That's about it! Enjoy...

@The_OGS

Hey man.. thanks for the comment.
Let's see how others react.

 

[jayraw]

Anyone else wanna comment? I ended up getting the hgst drive. Haven't received yet.

 

[jaguarskx]

I use Western Digital RE enterprise series hard drives in my home PC because they have statistically higher operational time before they fail.

 

[popatim]

They are usually built to more rigorous standards, have better vibration correction, are built for raids, and usually also have a higher mtbf with a much lower error rate.

 

[fzabkar]

Enterprise drives usually implement Error Recovery Control. WD calls it TLER (Time Limited Error Recovery), while Samsung and Hitachi refer to it as CCTL (Command Completion Time Limit).

ERC is of benefit in a RAID environment but some people may consider it to be detrimental in a desktop.

If a drive requires an excessive amount of time to read a difficult sector (usually 7 seconds), then it will give up rather than allowing the RAID controller to time out and drop the drive from the array. A desktop drive OTOH will keep trying until its retry count is exhausted.

 

[jayraw]

Enterprise drives usually implement Error Recovery Control. WD calls it TLER (Time Limited Error Recovery), while Samsung and Hitachi refer to it as CCTL (Command Completion Time Limit).

ERC is of benefit in a RAID environment but some people may consider it to be detrimental in a desktop.

If a drive requires an excessive amount of time to read a difficult sector (usually 7 seconds), then it will give up rather than allowing the RAID controller to time out and drop the drive from the array. A desktop drive OTOH will keep trying until its retry count is exhausted.

@fzabkar Thanks for the explanation. Still kind of in the dark. Will you help?
On my end I understand it as something to be worried about!!
Sorry about my lack of understanding.. Is giving up trying to read the difficult sector
a bad thing or a good thing when compared to the desktop drive's actions in a desktop set up in ahci (not raid)? What are the implications?

 

[jayraw]

@popatim, @jaguarskx

thanks for response. awesome. I ended up purchasing the hgst drive because of these characteristics.
At the same time.. I am still trying to figure out may be these aren't really suitable for desktop?
@fzabkar has good response..

 

[fzabkar]

I'm not the best person to answer your question, but FWIW here is Wikipedia's opinion:

http://en.wikipedia.org/wiki/Error_recovery_control#Desktop_Computers_and_TLER_Effect

If you can disable ERC/TLER/CCTL on your enterprise drive, then it will function just like a desktop drive in that respect. Personally, I would still prefer an enterprise drive, but you would need to be mindful of the ERC caveat.

Tools such as HDAT2 can disable or configure ERC, but I don't know if such changes survive a power cycle. WD has a tool called WDTLER that can configure the TLER setting for certain models.

 

[jayraw]

Thanks for the response anyway.

So, what is the implication when not used in raid? I mean CCTL stops the drive from trying to read difficult sector. Then what?

 

[fzabkar]

I guess it depends on the importance of a particular file. If it's an OS file, then I guess a BSOD might occur. If it's a JPG or MPEG, then perhaps you'll notice a problem in the image or a jump in the video, or maybe your application will simply abort loading the file.

Sorry, I really don't know.

 

[popatim]

Odds are that if it cant read the cluster in 7 seconds its bad anyways.
Plus Hitachi's usually let you set it manually. I'mnot positive about the current situation as they have been bought by WD. You'll find out soon enough<Grin> be sure to test if the change survives a power cycle (full shutdown then power back on)

 

[jayraw]

yeah.. laugh it up man.. lol

After I get the drive I'll run some tests.. see how it works in normal conditions. Do benchmark. I'll post everything here.
Then I might try change the cctl settings IF you guys have some sort of guide for that. Its the HGST A7K2000,
in case somebody has a guide.

 

[jayraw]

So I have been testing out the enterprise drive for a few days. I'm not seeing any boost in performance. Matter of fact.. in HD tune benchmark, my regular hdd performed same as the enterprise drive. The warranty if its valid then its a worthwhile purchase.

I am also seeing some smart data that's weird (hdd sentinel). The spin up time started at 19,xxx,xxx. The numbers are moving up slowly now around 20,xxx,xxx. while my regular drive remains around 16,xxx,xxx. I will flip the hdd and see if the numbers change. But I am obviously not seeing any difference in performance.. since the change in these numbers are probably in mili seconds or smaller.

Does anybody know how to change the cctl settings for this drive?

 

[popatim]

smartctl utility which is part of smartmon tools if it will work at all.