Quote:
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Originally Posted by netwraith
This probably won't be much of a problem. The reason for this is that controller is actually on the drives.. and as such, it is a synchronous process. The processor will need to wait for the controller to respond regardless. The addition of a bit of delay will slow things down a tad, but, I doubt that it will be very noticeable with the Intel NetBurst processors and GigaEther...
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I disagree, and can back it up with experience...
This "tad bit of delay" is exactly the problem.
Striped RAID arrays are sensitive to timing. Anyone who has spent a great deal of time using Striped RAID arrays will tell you this.
Here is just one (of many) examples:
(coming from Western Digitial Knowledgebase Answer ID 913)
Question
Why do EIDE drives disappear from the IDE RAID array or system after a short period of error-free operation?
Answer
Problem:
WD EIDE drives are dropped from an IDE RAID array or system after several days or weeks of error-free operation.
Solution:The problem is a result of a feature that reduces idle acoustic noise in desktop drives. This feature may cause a timeout likely (though not exclusively) in an IDE RAID environment. To disable the feature, you can run a simple Western Digital utility to turn off a single bit in the drive’s run-time configuration. Disabling of this feature will NOT impact normal system operations. No firmware or hardware changes are required.
This is just one example. In this case, the acoustic setting of the drive can cause perodic slow downs of the data flow and cause the RAID to time out.
I will say it one more time.
Striped RAID arrays ARE sensitive to timing. This is fact, not speculation. If the timing is off, a drive can drop out of the array as failed with no real data errors. I have seen this happen with different drives of the same size not having timing close enough and one of the drives dropping out all the time because of it.
I AM NOT SAYING these PATA to SATA adapters won't work. If the drives are the same, and the adapters are the same, the timing may very well stay within tolerances. All I AM SAYING is that these adapters do add yet another timing into the mix and MAY cause problems for your STRIPED RAID ARRAYS. BE CAUTIOUS! KEEP BACKUPS!
Many people, including myself, here on this forum like to experiment just for the experience of the experiment. No problems here with that. But not everyone likes to ride on the edge or can afford to do so. Thus where my problem comes in is when someone/anyone says, "such and such can be done" like a blanket statement without putting in the extra little information like the risks and when it won't work etc, or makes the assumption (incorrectly) that it will work in all cases.
My problem with this is for people who come to this forum for help and answers that may not know these technicalities or know any better and follow those blanket statements and then get burned by it. In this case, good EIDE/PATA drives are available up to 750 GB sizes and there is no good reason to use SATA drives with adapters other than to experiment. And, if your need goes over the 750 GB drives (and you can afford those 1GB and maybe larger drives), then you can afford a unit that was designed for them. Simple logic.
I am NOT against experimentation. I am all for it. But when you post that type of information, make sure you post the risks that go with it so those who may not know any better won't get sucked into a bad situation for them. That was my reason for posting what I did. So don't get all defensive. What I posted is FACT, and needs to be there to protect the inocent sorta speak.