On Wed, 16 Jan 2008 13:26:14 +0800, Shaohua Li said: > On Tue, 2008-01-15 at 22:56 -0500, [EMAIL PROTECTED] wrote: > > Do you have any numbers on what the added latency is for powersave mode, and > > a rough idea of how quickly chipsets will drop to low-power? It may affect > > usability a lot if it's "adds 10ms latency after 100ms idle" or "adds 100ms > > latency after 5 seconds idle" or some other pattern... > > > > (The chipset in my laptop claims to be an 82801G with 4 PCI-Express ports on > > it - I'm trying to get a rough idea what usage I'd get out of that > > feature..) > No, I thought to get the latency impact with ASPM enabled, but haven't > found a way to measure it. This is why the default setting of ASPM > currently is using BIOS setting.
It's OK - I spent some time staring at the output of 'lspci -t' on this laptop, and convinced myself that the numbers won't matter that much - of the 4 PCIE ports alledged to be there, 2 aren't connected to anything, and the other 2 are network (a tg3 and an intel 3945) - and those two are both either (depending where I am) "essentially idle and will almost certainly sleep" or "busy enough they likely won't sleep no matter *what* the numbers are". (That's assuming the chipset in question even *does* ASPM - but it wouldn't be the first time I've tested stuff just to make sure it didn't enable an impossible hardware option.. ;)
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