Re: [PROBLEM] Hw problem or software bug? DMA: Out of SW-IOMMU space....

From: Giangiacomo Mariotti
Date: Sun Dec 07 2008 - 16:38:27 EST

On Sun, Dec 7, 2008 at 7:47 PM, Robert Hancock <hancockr@xxxxxxx> wrote:
> Seems like you have lots of disks, it could be you just have too much IO in
> flight at the same time for the size of the IOMMU area. You might be able to
> avoid that by increasing the SW-IOMMU size.
> However, your system should be AHCI capable, you should try to switch the
> SATA controller into that mode in the BIOS (possibly labelled RAID mode or
> something). Then it shouldn't need to use bounce buffers for disk access in
> the first place (plus give you NCQ support).
I've done what you said, now is there anything I can do to see if the
problem is solved? Use some program which produces a lot of IO? Is
there any suggested IO stress test available?
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