Re: [dpdk-dev] [PATCH 2/2] fib: announce experimental tag removal of the fib API

["Medvedkin, Vladimir" <vladimir.medvedkin@intel.com>]

Hi Jan,

The RIB is always used as a control plane struct intended to maintain 
the correct content of the dataplane struct, such as DIR24_8 for 
example. So it is always used on _add()/_delete(). For simplicity you 
can consider it as an LPM's rule_info. But instead of keeping routes in 
a plane array as it is in LPM, FIB uses RIB which is more suitable 
binary tree.


On 05/08/2021 15:14, Jan Viktorin wrote:
> On Thu, 5 Aug 2021 15:08:13 +0200
> Vladimir Medvedkin <vladimir.medvedkin@intel.com> wrote:
> 
>> This patch announces the experimental tag removal of all fib APIs,
>> which have been experimental for 2 years.
>> API will be promoted to stable in DPDK 21.11
> 
> Hi Vladimir,
> 
> I have a question related to FIB. I am just learning how to use it and
> I found that each FIB always creates a new RIB internally. There is no doc
> about this topic...
> 
> If I understand correctly, the underlying RIB is only used when
> dummy_lookup() and dummy_modify() are used. But they are only used when the
> configured mode is RTE_FIB_DUMMY. Is there any reason to create the RIB with
> RTE_FIB_DIR24_8?
> 
> The issue with this is that each RIB allocates a new mempool internally which
> can waste quite a lot of never used memory that would be unused with DIR24_8
> implementation.
> 
> Regards
> Jan
> 
>>
>>
>> Signed-off-by: Vladimir Medvedkin <vladimir.medved...@intel.com>
>> ---
>>   doc/guides/rel_notes/deprecation.rst | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/doc/guides/rel_notes/deprecation.rst
>> b/doc/guides/rel_notes/deprecation.rst
>> index afb599a..58826a8 100644
>> --- a/doc/guides/rel_notes/deprecation.rst
>> +++ b/doc/guides/rel_notes/deprecation.rst
>> @@ -195,3 +195,5 @@ Deprecation Notices
>>     communicate events such as soft expiry with IPsec in lookaside
>> mode.
>>   * rib: The ``rib`` library will be promoted from experimental to
>> stable. +
>> +* fib: The ``fib`` library will be promoted from experimental to
>> stable.

-- 
Regards,
Vladimir