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On Wed, Aug 31, 2011 at 7:58 PM, Adam Carter <adamcarter3@×××××.com> wrote: |
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>> I just might have an opportunity to setup a Gentoo |
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>> System using 10 G ethernet (fiber). The .39 |
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>> kernel lists this hardware [1]. |
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>> |
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>> Does anyone have any experience with this hardware? |
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>> Does it work? Did you make any bandwidth measurements? |
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>> What type of fiber (mulimode/singlemode) (ST/SC) did you |
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>> use? |
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>> |
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>> Any comments? Is the kernel a bottleneck or your application? |
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> |
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> Intel are active in linux kernel development and their linux drivers |
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> seem to be very good. |
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> |
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> When testing Intel copper gig interfaces on an intel firewall (HP |
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> DL380G5 8 core box), I was able to send a core to 100% with ~330Mb of |
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> small packets. The limiting factor appears to be packet rate, and the |
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> consequent processing of interrupts (1 irq to 1 core). I don't think |
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> that a 10Gig interface would pass any more than that due to similar |
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> limitations. |
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> |
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> Tweaking the e1000 driver options RxDescriptors, TxDescriptors and |
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> RxIntDelay pushed it up to ~350Mb. MSI was enabled so no interrupt |
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> sharing. |
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> |
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> So if you're running normal sized packets, you should be ok. Otherwise |
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> you way want to look at what irqbalance can do for you (I didn't try |
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> it at the time). |
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> |
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> Also don't forget stuff like Large Receive Offload in your kernel. |
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I've overheard IRC conversations that discussed multi-queue network |
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cards in the context of multi-core systems. My educated guess, based |
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on what you mention, is that each queue in the card would ping a |
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different interrupt. Each interrupt might be handled by a different |
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core, so you'd see a scaleable improvement there. |
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|
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|
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-- |
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:wq |
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