[Eda-dev] Problems with qrouter getting stuck

Øyvind Harboe oyvind.harboe at zylin.com
Mon Oct 16 09:38:35 EDT 2017

Hi Tim,

thanks for the quick response. Comments inline below:

On Mon, Oct 16, 2017 at 2:22 PM, Tim Edwards <tim at opencircuitdesign.com>

> Hello Øyvind,
> I'm having a problem with qrouter getting stuck. It has been stuck on the
>> last line for 12 hours.
>> Any tips on how I might go about debugging this?
>> I've managed to get smaller designs through. Am I running into some sort
>> of
>> limit?
> Possibly.  From your output dump, I see you are using version 1.3.33,
> which is almost two years out of date (on what is a very actively
> developed program).  In the past year, I have made significant changes
> that have increased speed and efficiency and lowered memory overhead.
> The most recent version (1.3.93) will run designs with more than 100,000
> gates (maybe much more;  I have not stress-tested it beyond that).
> I expect the problem will go away with an update.  However, some of your
> questions have answers that are more nuanced than just "go update
> qrouter", so please see below.

Ah. I did build and install a newer qrouter in /usr/local/bin, but qflow is
picking up an older version.

What I did was first to install qflow w/apt-get install qflow, then build
qrouter locally. I guess I have to uninstall qflow, magic, qrouter and
graywolf, then build the tools that qflow depends on first, then qflow?
I'll give that a try.

$ qrouter -noc
Qrouter detail maze router version 1.4.2.T
No .cfg file specified, continuing without.
No Top-level Tk window available. . .

> Thoughts:
>> *Is there a limit to the number of input/output bits I can have on the top
>> level design?* I'm using osu018 and I have LOTS of top level input/output
>> pins. I'm primarily after numbers on size and clock frequency at this
>> point, so I'm passing a mock design to qflow to try to get it to give me
>> numbers.
> There will be some limit at which there are more pins than room around
> the layout perimeter to place them, in which case qflow may start stacking
> them outside of the layout where they end up outside of the routing grid.
> This is more likely to happen with pin constraints given to graywolf, such
> as attempting to place all pins on one side of the layout.

I don't have any constraints currently, so I'm leaving this one be for now.

> *Is the error message below relevant?* I don't think the error message is
>> important. It's probably just from this line "if [ ${TERM:=""} = "cygwin"
>> ]; then" statement in qrouter. If that statement fails, then it won't run
>> the cygwin hack, which is fine, I'm running under Ubuntu 16.04.
> No, that won't have an effect, but it is an interesting error.  What OS
> are you using?  Most Linux systems map /bin/sh to /bin/bash, and the
> syntax is probably a bash-ism.

Ubuntu has dash as default. I guess the qrouter scripts should either
specify #!/bin/bash or support dash?

$ ls -l /bin/sh
lrwxrwxrwx 1 root root 4 Sep  6 14:07 /bin/sh -> dash

>  From "top", I can see that the qrouterexec process is still busy. It is
>> using 45GByte, I only have 64GByte swap on this machine. Too little?
> The memory overhead problem was the biggest problem with qrouter until
> I found a good way to overcome it in revision 76.  Since then, qrouter
> runs with a much lower and more predictable memory overhead.

Another reason to upgrade! :-)

> I'm can't provide the entire design, but I'm happy to provide any other
>> information that would be helpful. I couldn't find a way to create an
>> account to register a bug in Bugzilla.
> Sorry, I couldn't find a way to prevent people from creating accounts
> in bugzilla and plastering it with spam, so I had to disable it.

There's not so much traffic in this mailing list that we can't afford to
discuss potential issues here first by way of triage?

>                                         Regards,
>                                         Tim
> +--------------------------------+-------------------------------------+
> | R. Timothy Edwards (Tim)       | email: tim at opencircuitdesign.com    |
> | Open Circuit Design            | web:   http://opencircuitdesign.com |
> | 19412 Cissel Manor Drive       | phone: (301) 528-5030               |
> | Poolesville, MD 20837          | cell:  (408) 828-8212               |
> +--------------------------------+-------------------------------------+

Øyvind Harboe, General Manager, Zylin AS, +47 917 86 146 <917%2086%20146>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.opencircuitdesign.com/pipermail/eda-dev/attachments/20171016/36a4abd7/attachment-0001.html>

More information about the Eda-dev mailing list