Usabilty of Twin Turbo Slots on rp5470 Server

[Fred G. Claypool, Jr.]

Hello everyone,

We've recently upgraded one of our rp5450 servers into an rp5470 server. We now realize that this rp5470 server gives us two "Twin Turbo" I/O slots (in positions 11 & 12), as well as six "Turbo" I/O slots (in positions 5-10).

We would like your recommendations regarding which of our I/O cards would most benefit from these "Twin Turbo" I/O slots.

Our current inventory, in no particular slot order:

1. A4800A, Single-Port FWD connected to an Autoloader 818 Tape Library
2. A4800A, Single-Port FWD connected to an mx600 Optical Library
3. A5158A, Fibre Channel Tachyon TL Adapter connected to an FC10 Disk Drive Enclosure (LCC A)
4. A5158A, Fibre Channel Tachyon TL Adapter connected to an FC10 Disk Drive Enclosure (LCC B)
5. A5158A, Fibre Channel Tachyon TL Adapter (currently not connected to anything)
6. A5230A, 10/100 Base-T LAN Adapter
7. A6795A, Fibre Channel Tachyon XL2 Adapter (currently not connected to anything, but planned to be in the future connected to our SAN Switch)

This server is running HP-UX 11i, in case that matters. Thanks, everyone, for your suggestions.

~Fred Claypool, Jr.

[Sridhar Bhaskarla]

Hi Fred,

11i does matter as it introduces "Hot swap" capability.

Turbo and Twin turbo slots are "hot pluggable" except that twin turbo slots are twice faster than turbo slots.

non-turbo slots are not 'hot pluggable' but that doesn't mean any card that is put in there can be hotpluggable as the driver should also support it. 'rad -q' will give you that information once all your cards are claimed in your ioscan output.

I would keep the storage cards in the high speed slots.

-Sri

[Sridhar Bhaskarla]

Hmm.. I think I should review my message atleast 100 times before I post it.. I should have written "turbo slots are "hotpluggable" but that doesn't mean any card in that slot is hotpluggable...".

-Sri

[Steven E. Protter]

I think the pain of moving around storage cards exceeds any possible benefit. I'm looking at the 5470 hardware right now as I specificy the next generation of machines for our shop.

If you run into a specific performance issue, then the cost/benefit ratio changes.

SEP

[Ted Buis]

Fred,

The A4800A are so slow, that there is not reason to waste a dual rope (twin turbo) slot on them. Since the fastest card you list is the A6795A, that would be the one to consider. I'm not sure that you will be able to notice a difference, however if I was starting from scratch, I would put the 2Gbit/sec FC cards in the twin turbo. However, if you are going into a 1Gbit/sec SAN switch or FC-AL device, then it would be used at the same speed as the A5158A's so it wouldn't make much difference.

[Zygmunt Krawczyk · Accepted solution]

Hi Fred,

"twin turbo" slots have 500 MB/s bandwidth.
"turbo" slots have 250 MB/s bandwidth.

some technical details of yours cards:

A4800A PCI HVD SCSI HBA
32 bit x 33 MHz = 132 MB/s PCI bus bandwidth
40 MB/s port bandwidth

A5230A PCI 10/100 Mbit/s Ethernet Adapter
32 bit x 33 MHz = 132 MB/s PCI bus bandwidth
200 Mbit/s in full-duplex mode = 25 MB/s port bandwidth

A5158A PCI FC 1Gbit/s HBA
64 bit x 33 MHz = 264 MB/s PCI bus bandwidth
200 MB/s in full-duplex mode port bandwidth

A6795A PCI FC 1Gbit/s or 2Gbit/s autosensing HBA
64 bit x 66 MHz = 528 MB/s PCI bus bandwidth
400 MB/s in full-duplex mode port bandwidth

So only A6795A card can take advantage of "twin turbo" slots.
Note, that rp5470 supports additional modern high performance
cards also, which can take dvantage of these slots. Some of them:

A7173A PCI-X 2 port Ultra320 SCSI HBA
A7143A PCI 4 port RAID Ultra160 SCSI
A9782A PCI-X 1Gb/2Gb FC / 1000Base-SX Combo
A9784A PCI-X 1Gb/2Gb FC / 1000Base-T Combo

Regards,
Zygmunt

[Ted Buis]

Actually the A4800A will only do 20MB/sec, because that is the limit for FWD SCSI.

[Zygmunt Krawczyk]

Note for Ted's response:

Yes, A4800A will only do 20MB/s with all external HVD devices. Actually the card is capable of working in 40MB/s Ultra SCSI mode also. This mode was used in V-Class Technical Server for internal HDDs.

Regards,
Zygmunt