Partial vs Full tables
baldur.norddahl at gmail.com
Mon Jun 8 08:14:17 UTC 2020
On 08.06.2020 07.56, Jakob Heitz (jheitz) via NANOG wrote:
> FIB compression comes with some risks.
> When routes churn, there are certain cases when you have to decompress the FIB.
> Then, the FIB must have the space, or else OOPS.
> If a set of compressed routes has to change to decompress some and compress a
> different set to improve overall compression, there is a lot of FIB
> programming going on. This can cause very long convergence times.
The easy solution is to introduce some delay before programming the FIB.
Or even process RIB updates as a separate thread, such that the FIB
update thread does not try to program every step the RIB might go
through. Instead the FIB update thread would take a snapshot of where we
are now and where do we want to be and only program the diff.
Given the concept is a smaller FIB size, this might actually end up
being less FIB programming.
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