Messages in this thread |  | | | Date | Thu, 26 Aug 2010 08:43:42 -0600 (Mountain Daylight Time) | | From | Marc Aurele La France <> | | Subject | Re: RFC: MTU for serving NFS on Infiniband |
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On Thu, 26 Aug 2010, Eric Dumazet wrote: > Le jeudi 26 août 2010 à 05:40 -0600, Marc Aurele La France a écrit :
>> Steady now. There's no need to YELL nor be arrogant. You and I both know >> there's a place for NFS over UDP. That's not changing any time soon. While >> I'm aware of the issue you brought up, it is separate from the one at hand in >> this discussion.
>> I do want to thank you, however, for reminding me of TCP. It's something >> 20/20 hindsight says I should have checked out before starting this thread. >> Logistically, it'll be a few days before I can do so though. If that allows >> me to increase the MTU all the way up to 65520, then this UDP thing will >> likely remain unresolved.
> Unfortunately, your infiniband device lacks NETIF_F_SG support.
Oh, the device itself probably has something similar, but ipoib (IP-over-Infiniband) doesn't export that capability.
> MTU a bit larger than PAGE_SIZE-overhead will need high order > allocations ?
Right. And a 65520 MTU allocates sk_buff's with 128K contiguous payloads.
Marc.
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