Performance of FC HBA

[Bart V]

Hello, I should need to put a FC card into a DL380 G5.
Digging into the quick specs of some cards I got completely confused


Which Card should give best transfer rate / performance?


A PCI-X FC HBA card or a PCI-e FC HBA card
I Doubt between a PCI-e and a PCI-X

Buss performance of PCI-e should be better than PCI-X?


HP StorageWorks PCI-e 4Gb Host Bus Adapter (AE311A)
Quick specs PCI-e FC card says :
“Throughput: 4 Gbps FC increases aggregate throughput rate to 800 MBps per channel in full-duplex mode.
Performance: PCI-Express host bus interface for high throughput applications.
High Transfer Rate: Minimum 150,000 IOPS per channel delivers high I/O transfer rates for storage applications.”

HP StorageWorks PCI-X 4Gb Host Bus Adapter (AD168A)
Quickness PCI-X FC card says :
“Superior performance capable of sustaining greater than 170,000 I/Os per second per channel (total, both ports) depending
on a server's processor and I/O capabilities.
4-Gbps FC increases aggregate throughput in excess of 1300 Mbytes per second depending on a server's processor and I/O
capabilities (total, both ports).”

I doubt between these 2 cards.

[TTr]

First the PCI-X card (AD168A) is a dual portcard so the 1300MB/s is for both ports. That is to compare it with the 800MB/s of the PCIe card which is single port.The 800 is a theoretical high of the FC protocol and the 1300 is really the 1600 theoretical high which is adjusted down to 1300 because of the limitation within the card due to the dual port switching.

(see the DL380 quick specs for a description of the PCi bus http://h18004.www1.hp.com/products/quickspecs/12477_div/12477_div.html )

Second, I assume that you have the mixed PCI cage which is PCI-X/PCIe combo. The PCI-x slots, slots 5 and 6, are 133MHz/64 bit which theoretically is 1064MB/s. This is much less than the 1300MB/s of the PCI-X dual port card. So if you have the dual port FC card and both ports are extremely active, you will not always get the maximum 800MB/s on either port.

The PCIe port in slot 3 is PCIe x8 and theoretically is rated at 4GB/s. Slots 1 and 2 are x4 at 2GB/s. So the PCIe card should give you better performance.

In the end based on the the typical i/o activities of the DL380 I don't think you will notice much of a difference with one card vs the other but it is always nice to get the bettwr performing components.

[asqwq]

hi
performance of pci-e is better than performance of pci-x
best regards
best regards