Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 3 Oct 2011 13:24:40 -0400
From:      Arnaud Lacombe <lacombar@gmail.com>
To:        mdf@freebsd.org
Cc:        freebsd-hackers@freebsd.org, satish kondapalli <nitw.satish@gmail.com>
Subject:   Re: NUMA Support is there in FreeBSD.
Message-ID:  <CACqU3MXrN-y6cpJ1_a=revBVGiCYHaUS1xmoqbzC_cfOa=pAwQ@mail.gmail.com>
In-Reply-To: <CAMBSHm_Gh26HaLfzmmkfNoQaCaqajxwVtHKm8s32aS1AneA80A@mail.gmail.com>
References:  <1317653757588-4865200.post@n5.nabble.com> <CAMBSHm_Gh26HaLfzmmkfNoQaCaqajxwVtHKm8s32aS1AneA80A@mail.gmail.com>

next in thread | previous in thread | raw e-mail | index | archive | help
Hi,

On Mon, Oct 3, 2011 at 12:31 PM,  <mdf@freebsd.org> wrote:
> On Mon, Oct 3, 2011 at 7:55 AM, satish kondapalli <nitw.satish@gmail.com>=
 wrote:
>> I am new to FreeBSD, I just want know whether FreeBSD supports NUMA.
>> If FreeBSD supports NUMA what are the kernel API to allocate memory?
>> is there any example driver or any driver which is using the NUMA API?
>>
>> please provide some inputs...
>
> The kernel is NUMA-aware (at least for x86),
>
What "x86" ? i386 ? amd64 ? both ?

> and memory is allocated
> round-robin amongst the memory domains. =A0There are not yet any KPIs
> for allocating memory in a specific NUMA domain, nor for binding
> specific threads / processes to get their memory local to a bound cpu
> instead of round robin.
>
I'm not sure to follow you. Say you have 2 memory domain attached to 2
different CPU package, each providing a memory domain, 4 physical core
and eventually 8 virtual. Say you have a network adapter supporting 8
RX/TX queue, dispatching RX packet to 8 netisr. Ideally, you'd want
those 8 queue/netisr to each have an affinity for a given CPU/memory
domain, have the network adapter route flow evenly on those those 8
CPU. Now, if you allocated an mbuf from memory domain 1, and end up
being processed by a CPU in domain 0, that likely to introduce
performance penalty.

Now, what about userland ?

This is certainly an horribly big picture :/

 - Arnaud

> There have been several discussions but no one has taken the lead and
> proposed some KPIs yet. =A0At $WORK the round-robin is sufficient to get
> consistent performance numbers and we have not yet started any
> experimentation with binding specific threads to either CPU or memory.
>
> Cheers,
> matthew
> _______________________________________________
> freebsd-hackers@freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-hackers
> To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org=
"
>



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CACqU3MXrN-y6cpJ1_a=revBVGiCYHaUS1xmoqbzC_cfOa=pAwQ>