[dpdk-dev] [PATCH] eal: add function to check if primary proc alive

[Van Haaren, Harry]

> From: Qiu, Michael
> On 1/25/2016 7:51 PM, Van Haaren, Harry wrote:
> > Not really, the secondary process will need some CPU,
> > however it can sleep so it doesn't have to use 100% of it.
> > It shouldn't be run on a core that is used by the primary
> > for packet-forwarding though - that will impact performance.
> 
> If not, what will happen if the primary been killed after you check
> alive? At that time, the secondary may be doing some work need primary
> alive.

What work are you thinking of? Apart from the shared config
and hugepages, primary and secondary processes are running
in their own address-space, and if the primary gets killed,
the secondary will notice when it next polls rte_eal_primary_proc_alive().

Whatever work the secondary was performing (in its own address space)
won't be directly changed by the primary being killed, because the
shared config and hugepages stay (EAL "cleans up" when the primary
is re-launched, not on quit).

-Harry