From: Philippe Gerum <rpm@xenomai.org>
To: xenomai@xenomai.org
Subject: Re: [Xenomai-help] How many cores Xenomai can support? how to extend to more cores, thanks!
Date: Thu, 17 Nov 2011 09:03:15 +0100 [thread overview]
Message-ID: <4EC4BFC3.1080603@domain.hid> (raw)
In-Reply-To: <C10D3FB0CD45994C8A51FEC1227CE22F369AEF2177@domain.hid>
On 11/17/2011 01:57 AM, Lou, Yuanzhi wrote:
> InXenomai’s native/task.h define as：
>
> #define T_CPU(cpu) (1 << (24 + (cpu & 7))) /* Up to 8 cpus [0-7] */
>
> #define T_CPUMASK 0xff000000
>
> Which means Xenomai only can support 8 cores at most?
The Xenomai core has no internal limit on the number of cores beyond the
one Linux defines by CONFIG_NR_CPUS. However, the locking model we use
has a low overhead (code and complexity) with few CPUs used in real-time
mode, at the expense of being sub-optimal with a large number of CPUs.
The API you mention simply reflects that fact.
Again: this design affects the number of CPUs used in real-time mode
(i.e. primary Xenomai mode), not necessarily the overall number of CPUs
present in the system and only available to regular Linux processing.
>
> BRs
>
> Lou Yuanzhi
>
>
>
> _______________________________________________
> Xenomai-help mailing list
> Xenomai-help@domain.hid
> https://mail.gna.org/listinfo/xenomai-help
--
Philippe.
prev parent reply other threads:[~2011-11-17 8:03 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-11-17 0:57 [Xenomai-help] How many cores Xenomai can support? how to extend to more cores, thanks! Lou, Yuanzhi
2011-11-17 8:03 ` Philippe Gerum [this message]
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