On Mon, Nov 16, 2020 at 08:24:48AM +0100, Thomas Monjalon wrote: > 13/11/2020 15:31, Juraj Linkeš: > > +option('max_lcores', type: 'integer', value: 0, > > + description: 'maximum number of cores/threads supported by EAL. Set to > > positive integer to overwrite per-arch or cross-compilation defaults. Set > > to -1 to detect the number of cores on the build machine.') > > +option('max_numa_nodes', type: 'integer', value: 0, > > + description: 'maximum number of NUMA nodes supported by EAL. Set to > > positive integer to overwrite per-arch or cross-compilation defaults. Set > > to -1 to detect the number of numa nodes on the build machine.') > > First comment: I don't like having so long description. > Second: I don't understand. > > It is said the default value is 0 so I expect it means automatic detection. > But later it is said -1 is for detection. So ? > Zero is for the "per-arch or cross-compilation default". This was discussed quite a bit in previous versions and this was te best compromise we could come up with. Having a default of auto-detect is definitely not something I think we should go with - just thinking of all the build CI jobs running on 2 or 4 core VMs! However, Juraj really felt there was value in having auto-detection, so it's set as a -1 value, which I'm ok with.
As I flagged in a previous mail thread, the whole config of DPDK builds is something we need to take a bigger look at in 21.02 and beyond. /Bruce