Re: ide and hot swap
Marc Merlin wrote:
While I'll be the last person to praise IDE, recent drives and controllers
have CRC error checking, which is actually better than parity.
OK, maybe this could shed some light on a mystery I'm fighting here with.
I recently replaced this (Asus P55T2P4) motherboard:
---
Oct 22 15:53:45 ruri kernel: PIIX3: IDE controller on PCI bus 00 dev 39
Oct 22 15:53:45 ruri kernel: PIIX3: not 100% native mode: will probe irqs
later
Oct 22 15:53:45 ruri kernel: ide0: BM-DMA at 0xe800-0xe807, BIOS
settings: hda:pio, hdb:pio
Oct 22 15:53:45 ruri kernel: ide1: BM-DMA at 0xe808-0xe80f, BIOS
settings: hdc:pio, hdd:pio
Oct 22 15:53:45 ruri kernel: hda: IBM-DTTA-351680, ATA DISK drive
Oct 22 15:53:45 ruri kernel: hdc: IBM-DTTA-351680, ATA DISK drive
Oct 22 15:53:45 ruri kernel: ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
Oct 22 15:53:45 ruri kernel: ide1 at 0x170-0x177,0x376 on irq 15
Oct 22 15:53:45 ruri kernel: hda: IBM-DTTA-351680, 16124MB w/462kB Cache,
CHS=32760/16/63, (U)DMA
Oct 22 15:53:45 ruri kernel: hdc: IBM-DTTA-351680, 16124MB w/462kB Cache,
CHS=32760/16/63, (U)DMA
---
It ran flawlessly and the disks showed no problems running with DMA
and delivering around 10MB/s or more with bonnie.
Now I replaced the motherboard (and nothing else like cables) with a
Tyan Trinity 100AT one:
---
Nov 7 18:25:51 ruri kernel: VP_IDE: IDE controller on PCI bus 00 dev 39
Nov 7 18:25:51 ruri kernel: VP_IDE: not 100% native mode: will probe irqs
later
Nov 7 18:25:51 ruri kernel: ide0: BM-DMA at 0xe000-0xe007, BIOS
settings: hda:DMA, hdb:DMA
Nov 7 18:25:51 ruri kernel: ide1: BM-DMA at 0xe008-0xe00f, BIOS
settings: hdc:DMA, hdd:DMA
Nov 7 18:25:51 ruri kernel: hda: IBM-DTTA-351680, ATA DISK drive
Nov 7 18:25:51 ruri kernel: hdc: IBM-DTTA-351680, ATA DISK drive
Nov 7 18:25:51 ruri kernel: ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
Nov 7 18:25:51 ruri kernel: ide1 at 0x170-0x177,0x376 on irq 15
Nov 7 18:25:51 ruri kernel: hda: IBM-DTTA-351680, 16124MB w/462kB Cache,
CHS=32760/16/63, UDMA
Nov 7 18:25:51 ruri kernel: hdc: IBM-DTTA-351680, 16124MB w/462kB Cache,
CHS=32760/16/63, UDMA
---
And promptly got this when putting some load on the HDs:
---
Nov 7 17:54:00 ruri kernel: hdc: dma_intr: status=0x51 { DriveReady
SeekComplete Error }
Nov 7 17:54:00 ruri kernel: hdc: dma_intr: error=0x84 { DriveStatusError
BadCRC }
Nov 7 17:54:00 ruri kernel: hda: dma_intr: status=0x51 { DriveReady
SeekComplete Error }
Nov 7 17:54:00 ruri kernel: hda: dma_intr: error=0x84 { DriveStatusError
BadCRC }
---
Turning off UDMA solves the problem and also halves the performance.
My questions are thus:
Did the old chip-set just use DMA (instead of UDMA) and thus didn't
triggers these problems?
If so, any way to put the VIA controller into plain DMA mode?
Or did the old chip-set no CRC checks and thus never noticed these problems?
But that should have caused some corruption and it never occured.
Dewa,
CB
--
// CB aka Christian Balzer, Tannenstr. 23c, D-64342 Seeheim, Germany
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Re: ide and hot swap
Gerrish, Robert [EMAIL PROTECTED] wrote: backups can save your business. You not only should think about system failures, but fires, floods, etc. and silent data corruption. Remember, IDE hasn't parity. Also, disk-drives can develop bad blocks over time. That's why incremental backups, even done on your old QIC-120 for only the most important files, can be good.
Re: ide and hot swap
On mar, nov 09, 1999 at 10:42:53 +0100, Marc SCHAEFER wrote: and silent data corruption. Remember, IDE hasn't parity. Also, disk-drives can develop bad blocks over time. While I'll be the last person to praise IDE, recent drives and controllers have CRC error checking, which is actually better than parity. Marc -- Microsoft is to software what McDonalds is to gourmet cooking Home page: http://marc.merlins.org/ (friendly to non IE browsers) Finger [EMAIL PROTECTED] for PGP key and other contact information
Re: ide and hot swap
While I'll be the last person to praise IDE, recent drives and controllers have CRC error checking, which is actually better than parity. would you happen to know which drives and controllers? The promise udma66's? Any WD IDE's or IBM's 36+gig. -sv
RE: ide and hot swap
Seth Vidal wrote: We've got DLT's doing backups right now and we're conceiving that it might be cheaper to setup a system with 2 or 3 linear striped or raid 0 34+gig ide disks and have 2 sets of these disks that we swap out week to week for backups - rather than spend a fortune in DLT tapes and deal with a whopping 4MB/s transfer time. We would be using a set of disks for 4 weeks then swapping out to another set - the other set would be fresh formatted at that point and would be ready to go for the next month's backups. Price wise, this seems like a good approach. If it were my system, I would be concerned about disaster recovery. I have been a believer for a long time in tape rotation and offsite storage. Also, you are risking losing 4 weeks worth of data; a full backup at least weekly and incremental backups can save your business. You not only should think about system failures, but fires, floods, etc. An onsite disk storage scheme doesn't take these situations into account. Perhaps, if you want to consider alternate storage, you should look at optical media or some other approach. Bob Gerrish
RE: ide and hot swap
Price wise, this seems like a good approach. If it were my system, I would be concerned about disaster recovery. I have been a believer for a long time in tape rotation and offsite storage. Also, you are risking losing 4 weeks worth of data; a full backup at least weekly and incremental backups can save your business. You not only should think about system failures, but fires, floods, etc. An onsite disk storage scheme doesn't take these situations into account. Perhaps, if you want to consider alternate storage, you should look at optical media or some other approach. but I'm talking about doing full rotations. Right now we're loading 7 tapes into the DLT jukebox and it rotates for a month through those. Then the level 0 tapes come out and go to my house for offsite storage. We start over (more or less) every month. I was proposing using 2 or 3 big ide's every month. We do risk losing 4 weeks from a fire but we Always have risked that. But all other storages are offsite. You risk losing whatever's in the room at the time of a fire. While 4 weeks is greater than 1 day it might be a tolerable risk. my biggest concern is MTBF and not fires. Fires are a mess but your data (while important) is not the first concern after a fire - rebuilding is. Its the random drive failures and overwrites that I think most backups protect from. -sv
