On 5/10/2012 8:51 AM, Phil Turmel wrote: > Hardware RAID cards usually offer battery-backed write cache, which is > very valuable in some applications. I don't have a need for that kind > of performance, so I can't speak to the details. (Is Stan H. > listening?) Yes, I'm here to drop the hammer, and start a flame war. ;) I've been lurking and trying to stay out of the fray, but you "keep dragging me back in!" --Michael Corleone I find the mere existence of this thread a bit comical, as with all others that have preceded it. I made the comment on this list quite some time ago that md raid is mostly used by hobbyists, and took a lot of heat for that. The existence of this thread adds ammunition to that argument. If not for the fact Western Digital added "TLER" to the spec sheet of it's RE and Raptor series drives many years ago, nobody would have every mentioned it. WD did this because those in the "channel" marketplace weren't buying the drives. They saw no difference with these new "enterprise" drives but the much higher price. WD has never sold RE/Raptor drives to server/storage OEMs. WD has never had a presence in enterprise storage. Seagate, Hitachi/IBM, Fujitsu, and to a small degree Toshiba, have owned that space for over a decade. So in an attempt to drive sales, they added "TLER" to the sheet to differentiate from their desktop drives. So what happens? All the hobbyists immediately want to enable this "TLER" feature from the "enterprise" drives on their consumer models, because "TLER" is all that makes them "enterprise" drives, after all, "all WD drives are the same, just with different firmware, right?". Proof point: Few write about this subject using the generic term "ERC", which is used by Seagate, or the term Samsung uses, "CCTL". Everyone seems to talk about "TLER". Hmmm... Coincidence? No, marketing. You won't find a single discussion about ERC/TLER/CCTL on any enterprise storage forum, unless its brought up by someone desiring to cut cost corners using consumer drives. So if md raid is not limited to use by hobbyists, and is indeed used in enterprise environments, then why aren't the enterprise boys discussing "the problems w/TLER and enterprise drives"? Because obviously md raid has no issues when being used with enterprise (ERC/TLER/CCTL) drives. Either that, or md raid is only used by hobbyists. ;) -- Stan -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
