http://forums.2cpu.com/showthread.php?t=57230
Controller Write Back Cache is ON
Drives Wite Through is ON
Controller Write Back Cache is ON
Drives Wite Through is ON
Loaded the latest and greatest BIOS/firmware package from IBM
7.12.12
http://www-304.ibm.com/jct01004c/systems/support/supportsite.wss/docdisplay?lndocid=MIGR-62540&brandind=5000008
The HD Tach now completes without error at a whopping 54 MB avg with burst of 90
The LSI adapter to external array is pulling down 145 MB avg with burst of 179
I'd really like to hear from IBm about this performance,
Check to make sure the controller is in the PCI-X 133 slot.
Looking at the manufacturers specs there are three PCI-X slots, two are 100 the other is 133. This probably isnt causing the bottleneck but you never know.
6. I cannot stand piece-by-piece servers. I have to maintain a list of support contracts and numbers, then every time an upgrade comes around, I have to make sure the whole kit works. I would think you would have applied your cost logic to this and see that assembling an entire server is not as cost effective as getting a vendor to do it (HP, Dell, whatever). However, this one makes me understand your warranty dilemma. I just go to the one vendor and say "XYZ is broken. Send a tech out." and the problem is fixed.
I have the 6M in one of the 100Mhz PCI-X slots. My LSI controller is in the 133 slot. I really don't see that as being the problem.
> PCI-Standard says "66MHz" to me when I read it, which doesn't make sense to me because there are no standard PCI slots on the board.
"standard PCI" historically means 32 bits @ 33 MHz = 133 MB/second MAX
(this is the same number as found in ATA-133 to describe PATA HDDs)
Supreme, Go work on your own forum, it appears to be read only!I do not intend to reveal to you
why I am participating in this forum.
Wait, let me try. No, Whizzard gets pissed because someone came into the thread trying to show how SCSI was more expensive then SATA, which DOESN'T help with his problem. When asked to either help or go away, the posted did neither. Did I get the problem right Whizzard???
Supreme, Go work on your own forum, it appears to be read only!Removed the NIC and no change....
My 133 MHz PCI-X slot is slot 6 as well. Server model is the x236 P/N 8841-01U tower with 6 bay hot swappable driver enclosure built into the front of the box.
Slots four and five are the PCI-X 100 Mhz
Slots two and three are PCI-Express
Slot 1 is 33 Mhz 32 bit PCI
I email'd IBM. We'll see what response, if any, I receive.
Put my 6M into slot six???? Why not....
I do not intend to reveal to you
why I am participating in this forum.
Oddly enough one of my searches for IBM 6M bottleneck returned this very post. 8O
Bah.
The tape drive is connected to the onboard SCSI controller. The adaptec chips just happen to be the same.
The ServeRAID card is in the PCI-X 133MHz slot (Slot 6).
I've not found a way to determine the channel speed because I'm using a backplane The UI won't report it for some reason if it's on a backplane. The BIOS was no help.
Back to square 1.
I'm starting to think it's a bottleneck on the board or the card at this point.
The serveraid 6M does use the Adaptec chip (AIC7902?)
But the motherboard has SCSI on it as well. There are SCSI ports on the motherboard for peripherals such as tape drives.
I would be shocked if the tape drive is plugged into the RAID controller, let alone the same channel. My understanding has always been the channel can used internally or externally, not both. Please correct me if that is incorrect.
I am kinda surprised by the negativity about IBM. Forget the Deathstar drives (consumer grade stuff) for a minute. With this exception of the 6M, I've had excellent success with their server grade equipment.
I don't think you can multiply 6 drives times 40 MB to get over 200MB/s with RAID 5. But I'm not a doctor or anything. I am running 5EE, which might be worse.
I will use the LSI card with the array that is connected to the 6M and see what results I get.
I intend to call IBM as well, but I might as well have some more fun first
Are you still averaging 55 to 60 MB/sec?