RE: [ECOS] Re: memory allocation

[Jing Luo <Jing at vicom dot com>]

Thanks.

And in the report, it mentions eCos don't support multiprocess and
multiprocessor.
Then how we handle the case for 8 CPUs in eCos's showcase?

And I found out eCos third party 3G LAB has solution for power management
and protected memory solution based on eCos.
How can I get the solution source code?

For commercial use of eCos, how much for the paid eCos customers? Do I need
to get eCos license?

-----Original Message-----
From: Jonathan Larmour [mailto:jlarmour@redhat.com]
Sent: Tuesday, January 29, 2002 5:25 PM
To: Jing Luo; 'Ravi Kumar B S'; 'ecos-discuss@sources.redhat.com'
Subject: Re: [ECOS] Re: memory allocation


Jonathan Larmour wrote:
> 
> Jing Luo wrote:
> >
> > Hi,
> >
> > I haven't got answer for the memory allocation and performance for eCos.
> >
> > For the MAX multi-thread eCos supported, I am not sure that eCos can
support
> > unlimited thread concurrently.
> >
> > I got the report on internet, it said the max thread priorities eCos can
> > support is 32. I don't know if it is changed.
> > http://www.dedicated-systems.com/encyc/buyersguide/rtos/Object153.html
> 
> Actually this is an interesting point as I see the basis for why it says
> that: CYGNUM_KERNEL_SCHED_PRIORITIES in the kernel configuration is
limited
> to 1 to 32. But for the mlqueue scheduler that restriction should not
> apply. You could just remove the "legal_values" line I'm pretty sure.

Actually I now think I'm telling porkies.

As it stands, it is restricted to 32 priorities (but you can have as many
threads as you like at those priorities).

The complication is the definition of cyg_sched_bitmap. But this is only
used in a small number of places and it would be very easy to write an
alternative but obviously less efficient implementation for when
CYGNUM_KERNEL_SCHED_PRIORITIES>32.

Jifl
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