Just for reference, here's the menu.lst entry from my menu.lst:

title           Ubuntu 9.04, kernel 2.6.31.4qemu
uuid            ab838715-9cb7-4299-96f7-459437993bde
kernel          /boot/vmlinuz-2.6.31.4qemu root=/dev/hda1 ro single 1
rootdelay=200

Everything look OK here?


On Wed, Mar 13, 2013 at 11:49 AM, Paul Rosenfeld <[email protected]>wrote:

> Nope, nothing fancy. A few commits behind HEAD on master with some
> modifications to the simulation (but nothing changed in qemu). Added
> rootdelay=200 and it hangs right after freeing kernel memory and takes a
> really long time to get the disks mounted and the devices loaded.
>
> I'll double check my image to make sure that the rootdelay made it into
> the correct menu.lst entry.
>
> The odd thing is that once I get to the login prompt (if I'm doing an
> interactive session), qemu is perfectly responsive. Maybe I'll try to boot
> a raw image instead of qcow2 to see if that changes anything.
>
>
>
> On Wed, Mar 13, 2013 at 11:43 AM, <[email protected]> wrote:
>
>> I forgot to add --
>>
>> The only issue that I can see with your approach is keeping qemu in sync
>> with ptlsim. If you look at `ptl_add_phys_memory_mapping` in
>> qemu/cputlb.c, you'll notice that qemu feeds page mappings to ptlsim even
>> when ptlsim isn't active.
>>
>> I could be wrong here, but I believe you'll need to update that mapping
>> once you boot a checkpoint.
>>
>> We'd be more than willing to help you in whatever way to can to get
>> something like this committed to master.
>>
>> Tyler
>>
>> > Paul,
>> >
>> > Adding rootdelay to menu.lst is the same thing as passing it as a kernel
>> > argument, so yes.... no difference.
>> >
>> > As Avadh mentioned, 5 hours is a _long_ time to get things going. I got
>> a
>> > 16+ core instance to get to a prompt in a few minutes last time I tried.
>> > Admittedly, I never tried to create a checkpoint when I had that many
>> > cores... is the checkpointing taking a long time, or are you waiting
>> that
>> > long just to boot the system?
>> >
>> > What value are you passing to rootdelay? You're building master without
>> > debugging or anything fancy, right?
>> >
>> > Tyler
>> >
>> >> I added rootdelay to menu.lst (and I think in grub1 you don't have to
>> do
>> >> anything else, right?)
>> >>
>> >> I'm using the old parsec images with a reasonably ancient ubuntu.
>> Should
>> >> I
>> >> be using something more recent?
>> >>
>> >>
>> >>
>> >> On Wed, Mar 13, 2013 at 11:13 AM, avadh patel <[email protected]>
>> >> wrote:
>> >>
>> >>>
>> >>>
>> >>>
>> >>> On Tue, Mar 12, 2013 at 1:19 PM, Paul Rosenfeld
>> >>> <[email protected]>wrote:
>> >>>
>> >>>> Hello Everyone,
>> >>>>
>> >>>> It's been a while but I'm starting to use MARSSx86 for simulations
>> >>>> again.
>> >>>> I've been trying to run 16 core simulations and am finding that the
>> >>>> boot
>> >>>> time is very long (~5 hours to make a checkpoint). This makes it
>> quite
>> >>>> frustrating when I accidentally set the wrong parameters inside the
>> >>>> workload or run the wrong workload or any number of other mistakes I
>> >>>> tend
>> >>>> to make.
>> >>>>
>> >>>> Booting 16 core should not take that long.  Did you try adding
>> >>> 'rootdelay' option to kernel command line? It significantly improves
>> >>> kernel
>> >>> boot time in QEMU for large number of cores.
>> >>>
>> >>> - Avadh
>> >>>
>> >>>
>> >>>> So I was thinking -- what if I made a post boot but
>> >>>> pre-simulation-switch
>> >>>> checkpoint (i.e., checkpoint but stay in emulation mode). That way,
>> >>>> the
>> >>>> create_checkpoints.py script could just launch the system from the
>> >>>> post-boot snapshot and proceed to launch the workloads which would
>> >>>> have
>> >>>> the
>> >>>> PTL calls that would then make the actual simulation checkpoints. Not
>> >>>> only
>> >>>> would that reduce the time it took to create a lot of checkpoints,
>> but
>> >>>> also
>> >>>> if I screwed up a checkpoint, I could just delete it, boot the
>> >>>> post-boot
>> >>>> snapshot, tweak the workload, and re-checkpoint the simulation.
>> >>>>
>> >>>> I think marss checkpoints piggyback on qemu's snapshot capabilities,
>> >>>> but
>> >>>> is there some downside to this approach here that I'm missing?
>> >>>>
>> >>>> Thanks,
>> >>>> Paul
>> >>>>
>> >>>> _______________________________________________
>> >>>> http://www.marss86.org
>> >>>> Marss86-Devel mailing list
>> >>>> [email protected]
>> >>>> https://www.cs.binghamton.edu/mailman/listinfo/marss86-devel
>> >>>>
>> >>>>
>> >>>
>> >> _______________________________________________
>> >> http://www.marss86.org
>> >> Marss86-Devel mailing list
>> >> [email protected]
>> >> https://www.cs.binghamton.edu/mailman/listinfo/marss86-devel
>> >>
>> >
>> >
>> >
>> > _______________________________________________
>> > http://www.marss86.org
>> > Marss86-Devel mailing list
>> > [email protected]
>> > https://www.cs.binghamton.edu/mailman/listinfo/marss86-devel
>> >
>>
>>
>
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