From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sarah Newman <srn@prgmr.com>
Subject: Re: [PATCH] net: bridge: add max_fdb_count
Date: Wed, 15 Nov 2017 20:54:05 -0800
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To: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>,
        Andrew Lunn <andrew@lunn.ch>,
        Stephen Hemminger <stephen@networkplumber.org>
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On 11/15/2017 08:05 PM, Toshiaki Makita wrote:
> On 2017/11/16 11:25, Andrew Lunn wrote:
>>> Also what do the vendors using bridge for L2 offload to switch think?
>>
>> The Marvell L2 switches which DSA supports have 8K FDB/MDB entries. So
>> maybe 1024 is a bit low?
> 
> How about U32_MAX by default since it is currently not restricted.
> (assuming the field will be changed to u32 as per Stephen's feedback).
> 
> Otherwise users may suffer from unexpected behavior change by updating
> kernel?
> 

U32_MAX seems like much too high a default to be helpful to a typical user. How many devices are realistically on a single bridge in the wild? Double
that seems like a reasonable default.

Additionally, since the exact limit seems controversial, it can be made a configuration parameter.

What about the rest?

--Sarah