Checking for TLER, ERC, etc. support on a drive

jgreco

Resident Grinch
Joined
May 29, 2011
Messages
18,681
So with TLER not working, ZFS would patiently wait for the read request to complete, right? But eventually it would give up and then what happens? If all I'm storing is static media that doesn't ever change (only new material is being added at a steady trickle), how big a deal is it if TLER does not work?

Desktop drives also typically error out after a short timeout, but that's more like maybe ~30-60sec. When you notice your filer acting twitchy, log in and look.

I deem the value of TLER on an archival pool (ISO's, static media, etc.) where delays in reads do not qualify as catastrophic to be a "nice to have" but typically the cheap drives don't have it. I find it cheaper to just have some spare drives and to replace twitchy drives if they develop problems.
 

pclausen

Patron
Joined
Apr 19, 2015
Messages
267
So when a desktop drive does error out after the ~30-60 seconds, does the data get written back to another block on the same drive from parity, or will data from that particular block be created from parity from that point on, until the drive is replaced?

In other words, using desktop drives means "one strike and you're out" so to speak, where TLER enabled drives can have "many lives" (determined by the number of spare blocks on-board).
 

jgreco

Resident Grinch
Joined
May 29, 2011
Messages
18,681
If ZFS reads a sector from disk and identifies it as in-error, it will immediately recompute the block from parity or recover it from mirror, depending, and then rewrite the incorrect sector in place.

The whole idea of a "scrub" is to force ZFS to read everything, which in turn causes it to correct any problems.

Enterprise drives develop errors too, so this is really only a matter of what happens next. A long timeout, or a much shorter one? I know that for my archive pools, I might be *annoyed* if it was acting slow, but I'll follow the same general steps of trying to rewrite a block to force a reallocation that I would do with an enterprise drive.

Typically I find that SMART long tests pick up the failures before ZFS does, but that's probably because I schedule two per week.
 

pclausen

Patron
Joined
Apr 19, 2015
Messages
267
Thanks jgreco. That all makes sense now and I feel much better about potentially picking up these 8TB My Books now. :)
 
Joined
Nov 11, 2014
Messages
1,174
Joined
Nov 11, 2014
Messages
1,174
Of course there is. It works for some drives. If you do not try to change it, then it's guaranteed that it won't be changed on ANY drives.

I wonder is there way to find out on particular drive if change really works ?
 

jgreco

Resident Grinch
Joined
May 29, 2011
Messages
18,681
I wonder is there way to find out on particular drive if change really works ?

Sure. Take off the top, take a pin, make a little scratch on one of the platters. Put it back together and give it a try.
 
Joined
Nov 11, 2014
Messages
1,174
Sure. Take off the top, take a pin, make a little scratch on one of the platters. Put it back together and give it a try.

I was hoping somebody already did that can share the results.:smile:
I am only interested to know about HGST 4TB Coolspin. Because this is the drive that make the most sense for me for price-quality-capacity and I have tons of them.
 

LIGISTX

Guru
Joined
Apr 12, 2015
Messages
525
Hey guys. I am trying to determine if this drive: HMS5C4040ALE640 (HGST MagaScale 4TB Coolspin) has CCTL capability.

It seems as though it does, this is from the product documentation, but it is a bit above my head: "When the device is in standby mode, Streaming Commands can’t be completed while waiting for the spindle to reach operating speed even if execution time exceeds specified CCTL(Command Completion Time Limit). The minimum CCTL is 50ms.CCTL is set to 50ms when the specified value is shorter than 50ms."

There is more mention of CCTL in the documentation: https://www.hgst.com/sites/default/files/resources/MSDC4000.B_OEM_Spec_r1.0.pdf but its over my head. This drive seems like such a great option! But I am trying to dive as deep as I possibly can before I make a purchase.
 

Spearfoot

He of the long foot
Moderator
Joined
May 13, 2015
Messages
2,478
Hey guys. I am trying to determine if this drive: HMS5C4040ALE640 (HGST MagaScale 4TB Coolspin) has CCTL capability.

It seems as though it does, this is from the product documentation, but it is a bit above my head: "When the device is in standby mode, Streaming Commands can’t be completed while waiting for the spindle to reach operating speed even if execution time exceeds specified CCTL(Command Completion Time Limit). The minimum CCTL is 50ms.CCTL is set to 50ms when the specified value is shorter than 50ms."

There is more mention of CCTL in the documentation: https://www.hgst.com/sites/default/files/resources/MSDC4000.B_OEM_Spec_r1.0.pdf but its over my head. This drive seems like such a great option! But I am trying to dive as deep as I possibly can before I make a purchase.
FWIW, the 'Coolspin' HGST drives are intended for use in desktop systems. HGST has the 'Desktop NAS' line of drives, which (along with their enterprise line of drives such as 'Ultrastar') target the NAS/server market and would be better suited for use with FreeNAS.

I don't know if the Coolspin drives do, but the Desktop NAS and Ultrastar drives both support TLER -- I use both, and posted about this subject upthread.

Good luck!
 

LIGISTX

Guru
Joined
Apr 12, 2015
Messages
525
SCT was disabled on my HGST UltraStar 7K4000 2T drives (HUS724020ALE640), and they didn't retain my new setting after a cold restart. So I added a post-init startup script to set it to 7 seconds.

I a somewhat confused by this. If I understand this correct, this is the full on enterprise level drive, and it doesn't seem to be set by default, and doesn't persist after a reboot?

If that is true, the fact the "cool spin" may not be set by default seems like a non issue.

Either way, would your script a few posts below work? If so, I would just utilize that.

But I also remember reading this thread last night and iirc a concern about weather setting this was *actually* doing anything anyways.

I think I am either thinking to much into this, or am confused. At 100 bucks a pop with 3 year warranty, the cool spin's just seem like a great value. And they are marketed as enterprise level, but not for "hot" data like the ultrastars. But I don't kid myself, I am not even close to "hot" enterprise level. I never delete anything from my array, so data isn't being rewritten often. Once it's on the array, it never leaves, and is not edited since it's mostly multimedia. It is read, but only written the original time, and I probably write ~2-4TB a year in actual data to the array. With accounting for scrubs etc, sure, the drives will be used, but to me this sounds exactly what they are marketed for.

Is the marketing "accurate" or just something the PR/marketing department decided to write on a nice little webpage, I have no idea lol.


Sent from my jailbroke iPhone using Tapatalk
 

Spearfoot

He of the long foot
Moderator
Joined
May 13, 2015
Messages
2,478
I a somewhat confused by this. If I understand this correct, this is the full on enterprise level drive, and it doesn't seem to be set by default, and doesn't persist after a reboot?

If that is true, the fact the "cool spin" may not be set by default seems like a non issue.

Either way, would your script a few posts below work? If so, I would just utilize that.

But I also remember reading this thread last night and iirc a concern about weather setting this was *actually* doing anything anyways.

I think I am either thinking to much into this, or am confused. At 100 bucks a pop with 3 year warranty, the cool spin's just seem like a great value. And they are marketed as enterprise level, but not for "hot" data like the ultrastars. But I don't kid myself, I am not even close to "hot" enterprise level. I never delete anything from my array, so data isn't being rewritten often. Once it's on the array, it never leaves, and is not edited since it's mostly multimedia. It is read, but only written the original time, and I probably write ~2-4TB a year in actual data to the array. With accounting for scrubs etc, sure, the drives will be used, but to me this sounds exactly what they are marketed for.

Is the marketing "accurate" or just something the PR/marketing department decided to write on a nice little webpage, I have no idea lol.


Sent from my jailbroke iPhone using Tapatalk
Would my script work with coolspin drives? I don't know... that depends on whether they have SCT support. You can always ask HGST technical support about it.

Should you buy the coolspin drives? That's up to you!

HGST has a good reputation for making high quality drives; my experience with them has been good. Chances are that the coolspins will work just fine for you... but I chose the NAS and enterprise drives, and that's what I recommend, if you're interested in my opinion. But I'm just another dog here typing messages on the internet! :)
 

LIGISTX

Guru
Joined
Apr 12, 2015
Messages
525
Would my script work with coolspin drives? I don't know... that depends on whether they have SCT support. You can always ask HGST technical support about it.

Should you buy the coolspin drives? That's up to you!

HGST has a good reputation for making high quality drives; my experience with them has been good. Chances are that the coolspins will work just fine for you... but I chose the NAS and enterprise drives, and that's what I recommend, if you're interested in my opinion. But I'm just another dog here typing messages on the internet! :)


Thanks for the info. I was able to find this in their pdf documentation:

Error Recover Control (SCT Command set)
When the device is in standby mode, any command where error recovery time limit is specified can’t be completed while waiting for the spindle to reach operating speed even if execution time exceeds specified recovery time limit. The minimum time limit is 6.5 second. When the specified time limit is shorter than 6.5 second, the issued command is aborted.

So, I think that means it should work with your script. I guess as you said, best option is to pick up the phone ;).


Sent from my jailbroke iPhone using Tapatalk
 
Joined
Nov 11, 2014
Messages
1,174
I don't know if the Coolspin drives do, but the Desktop NAS and Ultrastar drives both support TLER -- I use both, and posted about this subject upthread.

If you refer to thread #26 where you said: "SCT was disabled on my HGST UltraStar 7K4000 2T drives (HUS724020ALE640), and they didn't retain my new setting after a cold restart." and that is consider SUPPORTED then I can confirm to whoever want's to know that is the same way with HGST Coolspins.

P.S. HGST Coolspins are the drives I use exclusively.
 

wblock

Documentation Engineer
Joined
Nov 14, 2014
Messages
1,506
For what it's worth, I picked up some of these 4TB, 5700 RPM drives a couple of weeks ago. One was DOA, possibly due to shipping. After getting a replacement, they seem fine. They are definitely warmer-running than WD Red 2TB drives, and not as quiet.
 
Joined
Nov 11, 2014
Messages
1,174
But I also remember reading this thread last night and iirc a concern about weather setting this was *actually* doing anything anyways.

That's what I also would like to know very much ?

Error Recover Control (SCT Command set)
When the device is in standby mode, any command where error recovery time limit is specified can’t be completed while waiting for the spindle to reach operating speed even if execution time exceeds specified recovery time limit. The minimum time limit is 6.5 second. When the specified time limit is shorter than 6.5 second, the issued command is aborted.

It could be just me, but I feel this doesn't tell me anything ?! If somebody can interpret I would like to know what is this saying ?

I guess as you said, best option is to pick up the phone ;).

That would be a funny story I would appreciate if you share with us. :smile:
I can almost hear Customer support saying: " SC....., What ? Did you have a problems with your Hard Disk ? Is there anything else I can help you today ? "
 
Joined
Nov 11, 2014
Messages
1,174
For what it's worth, I picked up some of these 4TB, 5700 RPM drives a couple of weeks ago. One was DOA, possibly due to shipping. After getting a replacement, they seem fine. They are definitely warmer-running than WD Red 2TB drives, and not as quiet.

I respectfully disagree with everything you said, except the fact that must be the shipping breaking your drive. I am assuming you are talking about HGTS Coolspins , I don't know about WD Red 2tb but, Coolspins are ruining in low 30 Degree Celsius temp, almost noiseless , and out of 50 drives running for 5 years I don't have a single bad drive.
 

wblock

Documentation Engineer
Joined
Nov 14, 2014
Messages
1,506
These are HGST #0S03359, 4TB, 5700 RPM Coolspin drives. I don't know what to do to convince you about the noise. They aren't loud, they just aren't as quiet as the 2TB Reds. Likewise, they are warmer than the 2TB Reds were in the same cabinet. The volume level I will swear to. The heat, I would be very surprised if I was wrong, but willing to believe objective measurements. It does not really matter, since the HGST drives are twice the capacity of the Red drives, so it's not a fair comparison.

Out of a small quantity of drives, I've had one WD Red die in a week, so the Coolspin drives are, so far, no worse.

Would I buy more of these? Maybe, but they are now discontinued.
 
Joined
Nov 11, 2014
Messages
1,174
Warm and Cool is a term of perception. Some people think 40 Degrees is too much , some 50 , some worried about 30. I rather have the data, meaning numbers, specs, etc and draw my own conclusions of good or bad , speaking as technical person. Advertisers are the ones trying to avoid real data so people who understand it can't compare. They want the people to "believe" the terms like "faster" , "cooler" "better", I am sure you know the point I am trying to make.

I am not sure which ones are discontinued the red or coolspin ? If you mean coolspin , this will be something new to me , since I seen batch from resents months. I really hope you meant the WD red ones to be the ones discontinued , not Coolspin , for my sake:smile:
 

wblock

Documentation Engineer
Joined
Nov 14, 2014
Messages
1,506
Warm and Cool is a term of perception.
Yes. In my perception, in the exact same machine, replacing 2TB Red drives with the 4TB Coolspin drives, they run warmer and louder. This surprised me. Maybe it should not have, given that they have twice the capacity.

I am sure you know the point I am trying to make.
Yes, but if I were that easily influenced by suggestion, the "Coolspin" drives would have appeared to be cooler.

I am not sure which ones are discontinued the red or coolspin
B&H shows the Coolspin drives as discontinued, replaced by the 7200 RPM version. I've seen people elsewhere say they are discontinued.
 
Top