On Sun, 4 Jan 2009, Roger Heflin wrote:
Matt Garman wrote:
Are you talking about using additional SATA controllers (i.e. via
add-on cards)? Or simply talking about the interconnect between the
southbridge and the northbridge?
Don't count on it, it depends on the specific setup of the MB.
I think you're talking about the former, i.e. the SATA controller
integrated in the southbridge generally ought to be fine, but if you
start adding additional controllers that hang off the south bridge,
their could be competition for bandwidth to the northbridge...
right? (And wouldn't the nvidia chips have an edge here, since they
have everything combined into one chip?)
Again, it depends on how much bandwidth was allocated internally in the chip
just because it is one chip does not mean that anyone actually allocated
enough resources to the given part of the chip, or even has enough feed to
the chip to support them all. The Seagate 1.5's will stream quite a bit
higher numbers than previous disks, so if one had several of them they could
overload the allocated bandwidth. Things build-into a given MB aren't
always connected at full speed often some of them are actually pci bus parts
and suffer from slow access, I would expect there to be similar tradeoffs
even in single chip cases.
Yup that is why you need to check the schematic for the motherboard before
you purchase as to which PCI-e are "shared" vs. "switched" vs. dedicated
Makes intuitive sense anyway; but in my case I'm really just curious
about the SATA controller integrated into the southbridge; not
concerned with additional SATA controllers.
The build-in intel ich series controllers vary from version to version on
exactly how fast that they are in this test, the newer ones are faster than
the older ones.
Agree, the Northbridge <-> CPU generally increases in speed each new chipset,
965 -> X38 -> X48 etc..
Is the "parallel dd test" valid if I do a raw read off the device,
e.g. "dd if=/dev/sda of=/dev/null"? All my drives are already in an
md array, so I can't access them individually at the filesystem
level.
Thanks for the feedback and info!
Matt
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