Re: Memory, IDE performance, idle speculation, THANKS!
Brace for long message...
Philip Blundell wrote:
> >Funny thing is, I compiled 2.3.35-rmk1 with
> >CONFIG_CMDLINE="mem=128M root=/dev/hda3 ide0=autotune ide1=autotune"
> >so it should see all 128M, right?
> Try passing that command line from NeTTrom instead. I'm not sure the
> Netwinder kernel takes any notice of CONFIG_CMDLINE.
Hmm, thought of that, but couldn't find any appropriate NeTTrom environment
variables... Oh, there's cmdappend. Duh! With "setenv cmdappend mem=128M" it
doesn't boot!! Now when I try to power down and back up, NeTTrom doesn't
start!!! It calculates the bogoMIPS, then says:
Memory: 124176k/126976k available (796k kernel code, 52k reserved, 1952k data)
Problem: block on freelist at 00000000 isn't free.
Kernel panic: task trying to sleep
In swapper task - not syncing
Okay, glad I waited a few minutes before sending this message. I unplugged
again, waited about ten minutes, and now NeTTrom is saying:
Memory: 11064k/12288k available (796k kernel code, 52k reserved, 376k data)
and then goes on its way. Funky! Tried mem=128M again just for fun, no boot.
And once again, NeTTrom kernel panics if I unplug and replug less than a couple
of minutes later. I think I been gipped...
So what's that NeTTrom business all about? Does my cmdappend make NeTTrom think
it has has 128M when it really has 64? But I didn't even save-all the
parameters, so it shouldn't know anything about that cmdappend change, right?
And one other question: how do I pass two kernel args on the command line? I
tried using single quotes and double quotes, and also using backslash-space
between the parameters, but it always only picked up the first argument, doing
things like "cmdappend 'mem=128M none" (from printenv) when I tried to
wrap all the args in single quotes...
> >Second, using hdparm -t /dev/hda in RedHat gives 4.07 MB/sec, in Debian
> >2.2.13 1.59 MB/sec (!), in Debian 2.3.35-rmk1 2.63 MB/sec. Is this
> >real? Any ideas on how we might get Debian kernel 2.2/2.3 up to the
> >RedHat kernel 2.0 level of IDE performance?
> See above. :-)
> Also you could try playing with hdparm to make sure that DMA, readahead,
> 32-bit transfers, &c. are enabled.
Cool. ide0=autotune in cmdappend does nothing. However, hdparm -c1d1 /dev/hda
picks it up to 6.23 MB/sec! Readahead was already set. Thanks, my disk is
suddenly >130% faster!
Funny- in RedHat, hdpart -c1d1 brings it from 4.07 to 6.20 MB/sec (neither was
set before). There must have been something else going on there in the first
Jim Studt wrote:
> The 200MHz SA110 (like netwinder) burn about 1 watt. Way back in May
> 1999 Intel issued a press release mapping out the next generation
> StrongARM at 600MHz and < 0.5watts. Sampling first half 2000. Looks
> like StrongARM is about half the cost of Crusoe.
Excellent. Forgot about that.
> I suspect there is room for Crusoe and ARM. You sure wouldn't want to
> run an IA32 emulator on ARM, but if you are running native the choice
> will depend on cost, power dissipation, and performance.
Thanks very much, this makes sense. Competition is our friend. :-)
Adam Powell http://lyre.mit.edu/~powell/
Thomas B. King Assistant Professor of Materials Engineering
77 Massachusetts Ave. Rm. 4-117 Phone (617) 452-2086
Cambridge, MA 02139 USA Fax (617) 253-5418