how to verify / check / turn on fastpath on Dell R720 + H710p?

Hi,

You are correct that FastPath is only available on the H710P and H810 (not the H710).

To check if your card 1000:005b card is a H710 or H710P, check the PCI subsystem vendor and device ID:

1028 1f30  PERC H710 Embedded

1028 1f31  PERC H710P Adapter

1028 1f33  PERC H710P Mini (for blades)

1028 1f34  PERC H710P Mini (for monolithics)

1028 1f35  PERC H710 Adapter

1028 1f37  PERC H710 Mini (for blades)

1028 1f38  PERC H710 Mini (for monolithics)

For the R720 yours will either be Embedded, Adapter, or Mini for monothics (i.e. not mini for blades).

I am not sure what OS you are on but you can do on Linux "lspci -vnn" or BSD with "pciconf -lv" to see the PCI devices with both the text and numeric description of the subsystem IDs. The text description will be wrong or absent if your pci.ids is out of date but you can still compare the numbers to the above.

If you do in fact have a H710P, in order for it to be used on a given virtual disk it must be set for write-through, no read ahead, and no background operations in progress, though from the megacli -ELF output I suspect that is actually a H710 not a H710P.

Let us know how it goes and what you find out!

Well, there was indeed an H710 in the server, and it is now been delivered as promised -- with an H710p.

So, now that we have an H710p, I still get this:

# megacli -ELF -ControllerFeatures -a0

This Feature is not supported

Exit Code: 0x01

I appreciate the info above on how to enable fastpath, but....

There surely must be some way to:

1) verify that fastpath is being used, by a "FASTPATH: ON" validation

and

2) proof that fastpath even exists on the card, with the above -ELF command

Does anyone have any idea how to validate that this card, which all docs claim should have fastpath -- does?

No one is using fastpath on Dell products? :/

Fastpath isn't a joke, and it is even advertised as a bell&whistle for several Dell cards -- including the H700 + H710p series.

How can one even validate that it is functional?

Thanks for your patience, I spent some time researching this and came up with the following:

Dell's hardware RAID cards with LSI chipsets do not support MegaCli ELF commands since part of marketing and branding includes management of optional firmware licensed features, and these cannot be changed after leaving the factory.

The FastPath license should be included in the H710P firmware and the feature is enabled by default when the license is present and cannot be disabled. Per LSI documentation ( www.lsi.com/.../MR_advanced-softwareevaluation-kit-3.0.pdf ) the per-virtual disk configuration required for Fast Path is write-through cache policy, no read-ahead, and direct (non-cache) I/O. It provides the commands to set these (for adapter zero, logical disk zero): megacli –LDSetProp WT Direct NORA L0 a0 . I don't find any information on how to verify that it is active.