Talk:Error recovery control

Confusing
Starting this article calling TLER a bugfix to a feature is confusing and not totally accurate anyway. When TLER is disabled, does that indicate that sector retry (on read) is not time limited or does it indicate that the drive will spend however much time it wants re-reading that sector? The article mentions that TLER is defaulted to 0 seconds for desktop hard drives, which tends to indicate the hard drive will not spend extra time reading a bad sector but that just isn't true: Western Digital hard drives have for many years spent several seconds trying to re-read bad clusters.

--Iambk (talk) 13:19, 23 May 2011 (UTC)

Not sure about default WD settings
My own RE and RE3 drives came with both read and write TLER enabled, as opposed to the article which says that RE drives come only with write TLER enabled. I'm not sure if this differs by model or something else, or the article is just wrong.

iustin (talk) 19:01, 3 February 2009 (UTC)

I am pretty certain that both the Raptor (WD1500ADFD) and the Raptor X (WD1500AHFD) come with TLER disabled.

http://www.storagereview.com/articles/200601/WD1500ADFD_2.html?page=0%2C1 http://www.xtremesystems.org/forums/showthread.php?t=111335

I also double checked with WDTLER.EXE on my own WD1500ADFD. By default, TLER is DISABLED on raptors.

Orphan Status
(June 2009) I believe this page is linked to enough suitable related subjects to no-longer be considered an orphan. Any objections? —Preceding unsigned comment added by 125.236.233.185 (talk) 01:26, 9 June 2009 (UTC)

Note about Intel RAID
Why is there a note at the bottom regarding Intel RAID when there's a number of other 'raid controllers', such as nVidia, that are also fakeraid? This doesn't seem pertinent to the page at all... —Preceding unsigned comment added by 216.221.92.251 (talk) 04:01, 30 September 2010 (UTC)


 * It would be useful if the section gave advice if this means that TLER is required or not in such 'fake raid' setups. The Intel Matrix or otherwise. -Dan  —Preceding unsigned comment added by 115.133.184.210 (talk) 05:31, 8 February 2011 (UTC)

Word of advise
Don't know where or how to put this. The article makes it sound like this is "nice" thing to have or something, well no. TLER is a MUST with a hardware raid controller (even if you do JBOD with it). Older WD drives (1.5TB or less) allowed you to enable/disable TLER regardless of factory settings. Yes, even older green drives. But newer drives do not accept the command at all, even Black ones. This means you can no longer make a hardware array with green or even black drives, they must be of the RE type now. I would like to know what the situation is with other brands. Non tler Software raid, of the mdadm type (not fake raid) should work fine as long as you DON'T USE A HARDWARE RAID CONTROLLER. See, even if you plug a single drive to a hardware raid controller without tler, it will mark it fault sooner or later (usually after a reboot...).

In short: Hardware raid controller needs TLER enabled, at least with Adaptec controllers. — Preceding unsigned comment added by 201.208.156.167 (talk) 13:46, 21 July 2011 (UTC)

Misleading
A drive that, even under quite heavy load, needs more than 7 seconds to remap a bad sector is not a drive that should hold your data. The remapping will cause severe performance issues and, vice versa, even under load it'll normally remap quickly and without trouble. If it doesn't manage, at least IMO this indicates something needs to be done. 2001:A60:113F:B801:B8E3:C9BD:D5D3:7CF (talk) 20:38, 6 August 2013 (UTC)

Misplaced focus on hardware RAID
There's no inherent difference between software and hardware RAID w.r.t TLER; what's relevant is that there's a higher layer in the storage stack that can manage the retry better than the disk itself. Doesn't matter if it's a "hardware" RAID controller (which is of course really just software running on an outboard controller) or host-based software RAID. — Preceding unsigned comment added by 50.93.222.138 (talk) 03:33, 21 September 2014 (UTC)


 * The article author seems to be one of those what suffers from the old lore misconception that host-based software raid is somehow a red-headed stepchild compared to hardware raid, even though, as well stated, there really isn't such a thing as hardware raid anymore. It's just a question of which CPU the software is running on, and is that better or worse for the desires, conventions and use cases of any particular user.  When it comes to raid controller cards, they definitely lose in the power efficiency battle compared to host-based software raid.  They also rarely have the ability to track "touched" blocks v. untouched blocks, and so can be at a severe disadvantage when it comes to repairing an array compared to some software raid systems and filesystem software raid ala ZFS and btrfs, to name a couple.  I also noticed recently that the ability to continue to use an array that is degraded or repairing is still a feature that you have to pay a little extra for.  On the plus side, battery-backed cache can be an advantage for some use cases, as well as the ability to commit such saved transactions to the disks after their power has been restored.  Oh, and of course in environments with error prone media like optical devices, having the CRC calculations done outboard can be helpful when the application software heavily utilizes the main CPU.  Recent raid cards seems to be able to implement a hybrid setup speeding up both writes and reads, which could be very helpful for certain use cases.  While ZFS can create a hybrid filesystem, its caching abilities are only an advantage when it comes to reads.  — Preceding unsigned comment added by 173.11.90.217 (talk) 21:16, 15 June 2015 (UTC)


 * Totally agreed, should improve the things; though, the while article could use much more work. &mdash; Dsimic (talk &#124; contribs) 17:54, 11 July 2015 (UTC)

The article is not called TLER
Since the article is actually called Error recovery control and Time-limited error recovery is merely a re-direct to it, shouldn't all mention of TLER within the article be changed to ERC so as to remove the heavy Western Digital bias? 83.104.249.240 (talk) 20:01, 8 December 2015 (UTC)

External links modified
Hello fellow Wikipedians,

I have just added archive links to 1 one external link on Error recovery control. Please take a moment to review my edit. If necessary, add after the link to keep me from modifying it. Alternatively, you can add to keep me off the page altogether. I made the following changes:
 * Added archive https://web.archive.org/20071103042201/http://www.samsung.com:80/global/business/hdd/learningresource/whitepapers/LearningResource_CCTL.html to http://www.samsung.com/global/business/hdd/learningresource/whitepapers/LearningResource_CCTL.html

When you have finished reviewing my changes, please set the checked parameter below to true to let others know.

Cheers.—cyberbot II  Talk to my owner :Online 14:10, 19 February 2016 (UTC)