2004-11-06 15:51:42

by Kalin KOZHUHAROV

[permalink] [raw]
Subject: WDC TLER (Time Limited Error Recovery) and linux kernel

Hello,

I was just browsing Western Digital's site and was looking at the new RAID edition SATA drives...

As I saw the followind note:
##
IMPORTANT: Because of the time-limited error recovery feature, this product is intended for server applications and is not recommended for use in desktop systems.
##

So I was wondering what exactly is it and how is software RAID affaceted by it...

For a quick overview of TLER:
http://www.excelmeridiandata.com/products/wd_raid_edition_drive.shtml

The "official" WDC info is here:
http://www.wdc.com/en/library/sata/2579-001098.pdf

You'll see that WDC talks about 8-second timeout by the host (RAID) adapter, but there is no such specification. Where did this 8s came from?
How is it implemented in software RAID? (haven't looked the source yet)

In other words is there any benefits or problems using TLER-enabled disks under linux (with software RAID)?
Anybody tired them?

Just some questions that came into my mind...

Kalin.

--
|| ~~~~~~~~~~~~~~~~~~~~~~ ||
( ) http://ThinRope.net/ ( )
|| ______________________ ||