On 15 Mar 2021, at 14:55, Kevin Traynor wrote:
Hi Eelco, thanks for reviewing.
On 15/03/2021 11:45, Eelco Chaudron wrote:
On 11 Mar 2021, at 16:04, Kevin Traynor wrote:
Previously auto load balance did not trigger a reassignment when
there was any cross-numa polling as an rxq could be polled from a
different numa after reassign and it could impact estimates.
In the case where there is only one numa with pmds available, the
same numa will always poll before and after reassignment, so
estimates
are valid. Allow PMD auto load balance to trigger a reassignment in
this case.
Signed-off-by: Kevin Traynor <[email protected]>
---
lib/dpif-netdev.c | 20 ++++++++++++++++----
1 file changed, 16 insertions(+), 4 deletions(-)
diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c
index 816945375..19a6ac2d9 100644
--- a/lib/dpif-netdev.c
+++ b/lib/dpif-netdev.c
@@ -4888,4 +4888,10 @@ struct rr_numa {
};
+static size_t
+rr_numa_list_count(struct rr_numa_list *rr)
+{
+ return hmap_count(&rr->numas);
+}
+
static struct rr_numa *
rr_numa_list_lookup(struct rr_numa_list *rr, int numa_id)
@@ -5601,8 +5607,14 @@ get_dry_run_variance(struct dp_netdev *dp,
uint32_t *core_list,
numa = rr_numa_list_lookup(&rr, numa_id);
if (!numa) {
- /* Abort if cross NUMA polling. */
- VLOG_DBG("PMD auto lb dry run."
- " Aborting due to cross-numa polling.");
- goto cleanup;
+ /* Check if there is just one NUMA with pmds,
+ * in that case estimates will be valid. */
+ if ( rr_numa_list_count(&rr) == 1) {
+ numa = rr_numa_list_next(&rr, NULL);
+ }
+ if (!numa) {
+ VLOG_DBG("PMD auto lb dry run."
+ " Aborting due to cross-numa polling.");
+ goto cleanup;
+ }
The checks look a bit miss-ordered? Would just adding the check, and
remove it if we ever support it, be more clear? So something like
this:
diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c
index 816945375..ed348782f 100644
--- a/lib/dpif-netdev.c
+++ b/lib/dpif-netdev.c
@@ -5598,14 +5598,21 @@ get_dry_run_variance(struct dp_netdev *dp,
uint32_t *core_list,
for (int i = 0; i < n_rxqs; i++) {
int numa_id = netdev_get_numa_id(rxqs[i]->port->netdev);
- numa = rr_numa_list_lookup(&rr, numa_id);
- if (!numa) {
+
+ if (rr_numa_list_count(&rr) > 1) {
Having more than one numa is fine in general. It only becomes an issue
for estimates if we can't get a pmd on the local numa and we need to
do
cross-numa polling. So we check it after we find that there are no
local
numa pmd cores available.
Now it makes sense, I misread the patch, for some reason I thought the
rr_numa_list_lookup() was removed.
So the patch looks good, I did not test it though…
Acked-by: Eelco Chaudron <[email protected]>
_______________________________________________
dev mailing list
[email protected]
https://mail.openvswitch.org/mailman/listinfo/ovs-dev
