On 01/22/2013 10:55 AM, Shmulik Ladkani wrote:
Thanks Vlad,
On Tue, 22 Jan 2013 09:31:43 -0500 Vlad Yasevich <vyasevic@xxxxxxxxxx> wrote:
I guess this might simplify the data structures involved, avoiding the
refcounts, etc...
The penaties are:
- memory
- aesthetics (?)
- inefficient if query is "give me the entire list of VLANs port P is
member of". But do we have such a query in bridge's code?
Yes. When a mac address is added to a port without an explicit vlan tag
we try to add it for every vlan available on the port.
I see.
Can't this be bypassed by adding a _single_ FDB entry whose VID value
denotes "member of ANY vlan" (value outside the valid 0-4095 range)?
Also, in the API, the user may request vlans configured on a port.
Personally I'd pay the penalty implementing this specific user request
in an inefficeint way, to acheive overall simplicity in core bridge
code.
But that's just my humble opinion, maybe others might spot drawbacks
taking this approach.
BTW, went through the ML, couldn't find the reason why dropped the
per-port vlan bitmap and replaced with a vlan list (after your RFC v2
patches). Care to explain what was your motivation?
I wanted to reduce the memory footprint and make it a bit more
extensible so if priority was ever added, it would be very simple to do.
I also had to play some ugly memory barrier games to make it less racy.
I thought that the list/hash code was cleaner.
-vlad
Regards,
Shmulik
