Hello,
On Tue, 10 May 2022, Julian Anastasov wrote:
> What I see is that the value 128 is good but using
> 32 (MAX_STEP in the test) gives good enough results (3% diff).
Looks like I forgot to add this example how to
reduce code under lock because add/del dest can run in
parallel with scheduling, something that is a drawback
in this solution:
+static void ip_vs_rr_random_start(struct ip_vs_service *svc)
+{
+ struct list_head *old = READ_ONCE(svc->sched_data), *cur = old;
+ u32 start;
+
+ if (!(svc->flags & IP_VS_SVC_F_SCHED_RR_RANDOM) ||
+ svc->num_dests <= 1)
+ return;
+
+ start = prandom_u32_max(min(svc->num_dests, 32U));
+ while (start--)
+ cur = cur->next;
+ spin_lock_bh(&svc->sched_lock);
+ cmpxchg(&svc->sched_data, old, cur);
+ spin_unlock_bh(&svc->sched_lock);
+}
Regards
--
Julian Anastasov <ja@xxxxxx>
