Re: External USB2 HDD affects speed hda

[Rene Herman <rene.herman@keyaccess.nl>]

Rene Herman wrote:

> David Brownell wrote:

> > The experiment: verify that only the RUN bit is set on your machine
> > too. If "Periodic" and/or "Async" bits are set, then the controller
> > is _supposed_ to be issuing DMA transfers over PCI, so less bandwidth
> > will be available. Otherwise, not.

[ snip ]

> and one after switching on the USB2 HDD, when the hdparm result for hda 
> has dropped to 42 MB/s:
>
> ===
> bus pci, device 0000:00:09.2 (driver 10 Dec 2004)
> EHCI 1.00, hcd state 1
> structural params 0x00002204
> capability params 0x00006872
> status a008 Async Recl FLR

Only see that "Async" now while rereading. Did you mean that one? If so, 
I'm right now catting the registers file and that "Async" is toggling on 
and off continuously. 4 cats in a row:

status 0008 FLR
status 8008 Async FLR
status a008 Async Recl FLR
status 0008 FLR

Rene.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/