[Kea-users] Performance with many subnets and reservations

[Marcin Siodelski]

Hi Tino,

We appreciate your feedback regarding performance of Kea. We're aware
that there are possible performance optimizations in that area. We may
possibly add it in the 1.4.0 release.

Marcin Siodelski
ISC

On 20.11.2017 09:59, Tino Lehnig wrote:
> We have deployed Kea 1.3 in our environment with ~300 subnets using the
> shared networks capability and I would like to provide some feedback on
> performance. Note: We exclusively use host reservations in a MySQL
> database. There are no dynamic address pools. Leases are stored in a file.
> 
> We are at point where everything is working fine, but I am concerned
> that Kea will probably not scale well with an increasing amount of
> subnets in its current design. When enabling the debug log, I can see
> that Kea queries the database multiple times for each DHCP request.
> There is one query for each configured subnet. This has quite the impact
> on processing time as each request causes 300 database queries in our
> scenario. Queries are small and the query cache keeps disk I/O at a
> minimum, but CPU utilization is fairly high for Kea and MySQL.
> 
> If it is possible at all, it would probably be better to have Kea do
> only one query for the whole hosts table instead of separate queries for
> each subnet. If you any other suggestions for me, I'd appreciate that as
> well.
> 
> Thanks.
>