SATA port0-3 native mode

[avianrand]

(see my member config for gear)

I just noticed this setting in the BIOS: "SATA port0-3 native mode"

It's set "disabled". I'm running 4 WD1002FYBS 1TB drives in RAID10. Everything seems to be running fine after a week or so.

Should I enable this? If I do, will I have to redo the array and copy everything back to it that I had from my other system? A couple of things I read indicated that there's not much benefit; things like hot swap, which is not important for me in this situation. Not sure about other issues.

Thanks

 

[bilbat]

I mention this briefly in the 'sticky', under the Sorting Out SATA section:

Another often confused issue: the "Native Mode" setting for the SATA controller; unless you are one of the six people who ever actually bought Windoze ME, you always want this setting at "Enabled" - it turns on interrupt sharing for the controller, and ME was the last version that did not support this...

To get a better 'grip', you might want to read this earlier post about the interrupt mechanism itself, before proceeding...

Now that you've looked at the 'skirt-tugging' example, I'll explain a bit of 'evolution'. Back in 'ye olden days', this 'skirt tugging' was a pretty limited thing, as there wasn't all that much hardware to handle, and it wasn't going all that fast. The interrupts were individual, physical and electrical 'lines' into a single chip; this chip 'saw' an interrupt, and gave the CPU its own 'skirt tug' - a single line going high, along with a three bit (8 ID) 'code' saying which interrupt had been 'hit'; this eight bit code then referenced a segment that stored, at startup, the 'jump vectors', or program addresses that contained the service routines for each respective interrupt. When the IBM PC architecture began, this was too limited, as they had new-fangled 'slots' you could (wondrously) fill with you own 'junque', they added a second controller chip, 'piggy-backed' onto the first, and added a bit to the jump-vector table decode, so you knew which chip went active. The interrupt lines were still dead-dumb hardware, however, set by fiddling with little jumpers (one per IRQ [interrupt request line], if your hardware was really advanced; a coded pattern of three or four if it wasn't!), and you became (all too) familiar with your machine's interrupt architecture - as you'd run out! You wanted new piece of crap "X" for your machine, but it only supported interrupt "Y" or "Z", and, dammit, I got a modem on "Y", maybe I could move my parallel port from 7 to 5 - no, wait, that won't work either, 'cause I've got so-and-so there, maybe I could... So, eventually, to get rid of the ton of constraints, and accommodate a flood of new hardware, they came out with PICs (programmable interrupt controllers), that were more versatile, and could allow those harware lines to be 'shared', while still identifying the 'originating culprit', and lately, APICs, (advanced programmable interrupt controllers) who could do the same, and even handle multiple processor's responses...

Long story, but that's what this BIOS 'bit' is doing - it's telling the harware whether there's a 'shareable' PIC there - so the interrupts can be 'shared out'; this is faster (how much, I couldn't guess), more versatile, and less failure prone (same caveat), but the one thing I'm not sure of is if an OS installed one way, will work properly once you've 'toggled' this setting - and the only way I can think of to find out - is to try it!

PS - BTW, this 'making your life simpler' comes at a cost: the interrupt mechanism, handlers, and exceptions comprise sixty-seven pages in 3A of the Intel S'ware Developer's manual, with another twenty-four devoted to 8086 emulation ('old-stuff' compatibilty) mode!!

 

[avianrand]

Okay, wow. Lots of good info. So it was "disabled" by default. It's clear that it should be enabled. Remember, my 2 SSD's are in RAID 0 on SATA 0/1 and my 4 WD1002FYBS HDDs that are RAID10 are on SATA 2/3/4/5 (all the Intel controller of course). Can I just enable it or will that foul up my drive configurations? Not much on my RAID 10 yet so that's no big deal but I really don't want to reinstall Windows and all my programs again since things are just getting settled in. What do I need to do?

 

[bilbat]

Well - they disable it, by default, as a 'fail-safe', fall-back position; an interrupt-sharing capable modern OS will work with sharing disabled - an older, non-sharing OS will not work with sharing enabled... Again, I don't know if it will work to 'toggle' it, with the OS already installed - my gut says it won't care, but I've never tried it, 'cause I've never had a reason to be in that situation. I doubt there'd be anything more serious than a BSOD - if that happens, go back into the BIOS and 'toggle' it back! As for RAID 10, you need four drives, and can only do it on a southbridge controller (or a RAID card with at least four ports) - best way to think of it is as a RAID1 'duplicated drive pair, then the whole shebang 'striped' across another pair for speed, as in RAID0[:lectrocrew:2][:lectrocrew:2]

 

[avianrand]

Okay. I'll give it a shot.

As for RAID 10, you need four drives, and can only do it on a southbridge controller (or a RAID card with at least four ports) - best way to think of it is as a RAID1 'duplicated drive pair, then the whole shebang 'striped' across another pair for speed, as in RAID0

Yes, I know what RAID 10 is. Like I said, I have 4 drives on it now, on the SATA 2/3/4/5 ports. All 6 ports (0/1/2/3/4/5) are on the Intel controller. What are you telling me here? I'm not following you.

 

[kbits]

Avianrand - As always, make sure you have your data on RAID10 fully back up before messing around with BIOS sata settings.

 

[bilbat]

If you have four drives already RAIDed, DL HD Tune, run it, post the resultant screen, and I'll tell you whether it's worth fiddling around with...

That backup reminder brings up something I might want to add to the 'sticky' - when you 'back up', if you have never done a restore, of at least some sizeable piece of data, you do not have a 'backup'! What you have is a fond hope that you might have a backup!! Follow the lead of the 'server guys'; check your method; do a restore to test, and, should there be any major revisions, to either your hardware, or your backup software, do it again - just to be sure!

 

[avianrand]

I changed the setting a few hours ago and rebooted. Seems to be fine. What I don't understand is why it's for SATA 0/1/2/3 and doesn't include 4/5 when they all on the same controller. My RAID0 SSD's are on 0/1 and 2 of my 4 RAID10's are on 2/3 but the other 2 are on 5/6.


Oh yeah! I know full well about test restores. Remember, I write custom database software. I had a client a few years ago that I wrote a mission critical db app for. He hired a hardware/networking company to come in and set up his new office when he moved. The server had a tape drive on it. He faithfully changed tapes whenever necessary and took them off site as well. He had a good routine going. I stopped doing any work for him after a few years because he was just plain too hard to deal with. It wasn't worth my time. A couple of years ago I got a phone call from him. His server failed. The HDD went bad . He contacted his hardware company to take care of things. They set up the new drive and went to a tape to restore his very critical business data he'd accumulated for the last few years. It turned out none of the backups were valid. He'd never tested any of them ever. He took the HDD to a local company to try to recover the data but they were unable to do so. He ended up going bankrupt and getting sued by several of his clients for not having the data on his system that he was obligated to have by law. It was a big mess. The reason he called me was to see if I had a backup of his data from the last time I worked on things. I didn't.

I'm always very adamant about data backups and test restores with my clients but you can only lead a horse to water.... So now I tell all my clients this story now so they don't get complacent with their data. Even still I found out that one of my clients that I had written a db app for about 9 years ago had never made a single backup in all that time. I had given them a backup routine on paper that showed when and how to make them and it included doing test restores. They must have circular filed it because they never used it. When I told them about this story they started burning a CD of the db data every day and taking it off site. Good thing too because the new server they recently put together had an unrecoverable drive failure. They were very fortunate that they never lost a drive during the time they were not making backups.

On a funnier note, I taught adult ed AutoCAD for a few years quite some time ago. It was community education and the budget was very limited. Our computers were pretty old and we were a few versions behind in AutoCAD and still running DOS. All of the computers were on daisy chained power strips on the floor. The desks were in rows of 10 or so and were back to back so each row was really 2 rows of 10 making for a total of about 20 in each row. I can't tell you how often I'd tell students to get in the habit of hitting CTRL+S every few minutes or so. They just didn't listen. Every once in a while I'd hear a gasp from several students. I'd look up to see a bunch of horrified faces and computers rebooting. What would happen is every so often somebody in the row would stretch his feet and kick off the power button on the strip under his table killing the power to everyone in the row. It's astonishing how many people would never save their work in an entire 3 hour 45 minute long class. Used to make me nuts!

By the way, I must have missed your

but the one thing I'm not sure of is if an OS installed one way, will work properly once you've 'toggled' this setting - and the only way I can think of to find out - is to try it!

yesterday due to fatigue. By the time I got through your dissertation ( ) on interrupts my eyes were a bit bleary. LOL. But thanks for the explanation. I remember having to deal with IRQ settings for some time and then it kind of just went away. I was thinking fondly about that last week as I was putting this new machine together. I never got deep enough into it to fully understand what was going. Just knew that it was a bit of a pain sometimes.