Hi Konstantin,
On 3/23/2026 3:48 PM, Konstantin Ananyev wrote:
Add VRF (Virtual Routing and Forwarding) support to the IPv4
FIB library, allowing multiple independent routing tables
within a single FIB instance.
Introduce max_vrfs and vrf_default_nh fields in rte_fib_conf
to configure the number of VRFs and per-VRF default nexthops.
Thanks Vladimir, allowing multiple VRFs per same LPM table will
definitely be a useful thing to have.
Though, I have the same concern as Maxime:
memory requirements are just overwhelming.
Stupid q - why just not to store a pointer to a vector of next-hops
within the table entry?
Am I understand correctly, a vector with max_number_of_vrfs entries and
use vrf id to address a nexthop?
Yes, this may work.
But, if we are going to do an extra memory access, I'd better to
maintain an internal hash table with 5 byte keys {24_bits_from_LPM,
16_bits_vrf_id} to retrieve a nexthop.
And we can provide to the user with ability to specify custom
alloc/free function for these vectors.
That would help to avoid allocating huge chunks of memory at startup.
I understand that it will be one extra memory dereference,
but probably it will be not that critical in terms of performance .
Again for bulk function we might be able to pipeline lookups and
de-references and hide that extra load latency.
Add four new experimental APIs:
- rte_fib_vrf_add() and rte_fib_vrf_delete() to manage routes
per VRF
- rte_fib_vrf_lookup_bulk() for multi-VRF bulk lookups
- rte_fib_vrf_get_rib() to retrieve a per-VRF RIB handle
Signed-off-by: Vladimir Medvedkin <[email protected]>
---
lib/fib/dir24_8.c | 241 ++++++++++++++++------
lib/fib/dir24_8.h | 255 ++++++++++++++++--------
lib/fib/dir24_8_avx512.c | 420 +++++++++++++++++++++++++++++++--------
lib/fib/dir24_8_avx512.h | 80 +++++++-
lib/fib/rte_fib.c | 158 ++++++++++++---
lib/fib/rte_fib.h | 94 ++++++++-
6 files changed, 988 insertions(+), 260 deletions(-)
<snip>
--
Regards,
Vladimir
