RE: [RFC PATCH] config: make queues per port a meson config option

["Morten Brørup" <mb@smartsharesystems.com>]

> From: Bruce Richardson [mailto:bruce.richardson@intel.com]
> 
> The default number of ethernet queues per port is currently set to
> 1k which is more than enough for most applications, but still is lower
> than the total number of queues which may be available on modern NICs.
> Rather than increasing the max queues further, which will increase
> the memory footprint (since the value is used in array dimensioning),
> we can instead make the value a meson tunable option - and reduce the
> default value to 256 in the process.

Overall, I agree that this tunable is not very exotic, and can be exposed as suggested.
The reduction of the default value must be mentioned in the release notes.


>  # set other values pulled from the build options
>  dpdk_conf.set('RTE_MAX_ETHPORTS', get_option('max_ethports'))
> +dpdk_conf.set('RTE_MAX_QUEUES_PER_PORT',
> get_option('max_queues_per_ethport'))

Please rename RTE_MAX_QUEUES_PER_PORT to _PER_ETHPORT, so it resembles MAX_ETHPORTS. For API backwards compatibility, you can add:
#define RTE_MAX_QUEUES_PER_PORT RTE_MAX_QUEUES_PER_ETHPORT


I wonder if it would be possible to have separate max sizes for RX and TX queues? If it can save a non-negligible amount of memory, it might be useful for some applications.


With suggested changes (splitting RX/TX maximums not required),
Acked-by: Morten Brørup <mb@smartsharesystems.com>