On Fri, Feb 23, 2018 at 2:03 PM, Ben Pfaff <b...@ovn.org> wrote: > > ofproto_port_open_type() was surprisingly slow because it called the > function ofproto_class_find__(), which itself was surprisingly slow because > it actually creates a set of strings and enumerates all of the available > classes. > > This patch improves performance by eliminating the call to > ofproto_class_find__() from ofproto_port_open_type(). In turn that > required changing a parameter type and updating all the callers. > > Possibly it would be worth making ofproto_class_find__() itself faster, > but it doesn't look like any of its other callers would be used in inner > loops. > > A different patch that was also meant to speed this up reported the > following performance improvements. That patch just eliminated half of the > calls to ofproto_class_find__() in inner loops, whereas this one eliminates > all of them and should therefore perform even better. > > This patch arises as a result of testing done by Ali Ginwala and Han > Zhou. Their test showed that commit 2d4beba resulted in slower > performance of ovs-vswitchd than was seen in previous versions of OVS. > > With this patch, Ali retested and reported that this patch had nearly > the same effect on performance as reverting 2d4beba. > > The test was to create 10000 logical switch ports using 20 farm nodes, > each running 50 HV sandboxes. "Base" in the tests below is OVS master > with Han Zhou's ovn-controller incremental processing patch applied. > > base: Test completed in 8 hours > base with 2d4beba reverted: Test completed in 5 hours 28 minutes > base with this patch: Test completed in 5 hours 30 minutes > > Reported-by: Mark Michelson <mmich...@redhat.com> > Signed-off-by: Ben Pfaff <b...@ovn.org> > --- > ofproto/in-band.c | 2 +- > ofproto/ofproto.c | 30 ++++++++++-------------------- > ofproto/ofproto.h | 2 +- > vswitchd/bridge.c | 12 ++++-------- > 4 files changed, 16 insertions(+), 30 deletions(-) > > diff --git a/ofproto/in-band.c b/ofproto/in-band.c > index 849b1cedaff0..82d8dfa14774 100644 > --- a/ofproto/in-band.c > +++ b/ofproto/in-band.c > @@ -428,7 +428,7 @@ in_band_create(struct ofproto *ofproto, const char *local_name, > struct in_band *in_band; > struct netdev *local_netdev; > int error; > - const char *type = ofproto_port_open_type(ofproto->type, "internal"); > + const char *type = ofproto_port_open_type(ofproto, "internal"); > > *in_bandp = NULL; > error = netdev_open(local_name, type, &local_netdev); > diff --git a/ofproto/ofproto.c b/ofproto/ofproto.c > index f28bb896eee9..a982de9d8db4 100644 > --- a/ofproto/ofproto.c > +++ b/ofproto/ofproto.c > @@ -1966,27 +1966,18 @@ ofproto_port_dump_done(struct ofproto_port_dump *dump) > return dump->error == EOF ? 0 : dump->error; > } > > -/* Returns the type to pass to netdev_open() when a datapath of type > - * 'datapath_type' has a port of type 'port_type', for a few special > - * cases when a netdev type differs from a port type. For example, when > - * using the userspace datapath, a port of type "internal" needs to be > - * opened as "tap". > +/* Returns the type to pass to netdev_open() when 'ofproto' has a port of type > + * 'port_type', for a few special cases when a netdev type differs from a port > + * type. For example, when using the userspace datapath, a port of type > + * "internal" needs to be opened as "tap". > * > * Returns either 'type' itself or a string literal, which must not be > * freed. */ > const char * > -ofproto_port_open_type(const char *datapath_type, const char *port_type) > +ofproto_port_open_type(const struct ofproto *ofproto, const char *port_type) > { > - const struct ofproto_class *class; > - > - datapath_type = ofproto_normalize_type(datapath_type); > - class = ofproto_class_find__(datapath_type); > - if (!class) { > - return port_type; > - } > - > - return (class->port_open_type > - ? class->port_open_type(datapath_type, port_type) > + return (ofproto->ofproto_class->port_open_type > + ? ofproto->ofproto_class->port_open_type(ofproto->type, port_type) > : port_type); > } > > @@ -2728,10 +2719,9 @@ init_ports(struct ofproto *p) > static bool > ofport_is_internal_or_patch(const struct ofproto *p, const struct ofport *port) > { > - return !strcmp(netdev_get_type(port->netdev), > - ofproto_port_open_type(p->type, "internal")) || > - !strcmp(netdev_get_type(port->netdev), > - ofproto_port_open_type(p->type, "patch")); > + const char *netdev_type = netdev_get_type(port->netdev); > + return !strcmp(netdev_type, ofproto_port_open_type(p, "internal")) || > + !strcmp(netdev_type, ofproto_port_open_type(p, "patch")); > } > > /* If 'port' is internal or patch and if the user didn't explicitly specify an > diff --git a/ofproto/ofproto.h b/ofproto/ofproto.h > index 1e48e1952aa2..8c85bbf7fb26 100644 > --- a/ofproto/ofproto.h > +++ b/ofproto/ofproto.h > @@ -290,7 +290,7 @@ int ofproto_port_dump_done(struct ofproto_port_dump *); > #define OFPROTO_FLOW_LIMIT_DEFAULT 200000 > #define OFPROTO_MAX_IDLE_DEFAULT 10000 /* ms */ > > -const char *ofproto_port_open_type(const char *datapath_type, > +const char *ofproto_port_open_type(const struct ofproto *, > const char *port_type); > int ofproto_port_add(struct ofproto *, struct netdev *, ofp_port_t *ofp_portp); > int ofproto_port_del(struct ofproto *, ofp_port_t ofp_port); > diff --git a/vswitchd/bridge.c b/vswitchd/bridge.c > index cf9c79fd77cf..f03fb567f0be 100644 > --- a/vswitchd/bridge.c > +++ b/vswitchd/bridge.c > @@ -88,7 +88,6 @@ struct iface { > > /* These members are valid only within bridge_reconfigure(). */ > const char *type; /* Usually same as cfg->type. */ > - const char *netdev_type; /* type that should be used for netdev_open. */ > const struct ovsrec_interface *cfg; > }; > > @@ -822,7 +821,9 @@ bridge_delete_or_reconfigure_ports(struct bridge *br) > goto delete; > } > > - if (strcmp(ofproto_port.type, iface->netdev_type) > + const char *netdev_type = ofproto_port_open_type(br->ofproto, > + iface->type); > + if (strcmp(ofproto_port.type, netdev_type) > || netdev_set_config(iface->netdev, &iface->cfg->options, NULL)) { > /* The interface is the wrong type or can't be configured. > * Delete it. */ > @@ -1778,7 +1779,7 @@ iface_do_create(const struct bridge *br, > goto error; > } > > - type = ofproto_port_open_type(br->cfg->datapath_type, > + type = ofproto_port_open_type(br->ofproto, > iface_get_type(iface_cfg, br->cfg)); > error = netdev_open(iface_cfg->name, type, &netdev); > if (error) { > @@ -1856,8 +1857,6 @@ iface_create(struct bridge *br, const struct ovsrec_interface *iface_cfg, > iface->ofp_port = ofp_port; > iface->netdev = netdev; > iface->type = iface_get_type(iface_cfg, br->cfg); > - iface->netdev_type = ofproto_port_open_type(br->cfg->datapath_type, > - iface->type); > iface->cfg = iface_cfg; > hmap_insert(&br->ifaces, &iface->ofp_port_node, > hash_ofp_port(ofp_port)); > @@ -3445,13 +3444,10 @@ bridge_del_ports(struct bridge *br, const struct shash *wanted_ports) > const struct ovsrec_interface *cfg = port_rec->interfaces[i]; > struct iface *iface = iface_lookup(br, cfg->name); > const char *type = iface_get_type(cfg, br->cfg); > - const char *dp_type = br->cfg->datapath_type; > - const char *netdev_type = ofproto_port_open_type(dp_type, type); > > if (iface) { > iface->cfg = cfg; > iface->type = type; > - iface->netdev_type = netdev_type; > } else if (!strcmp(type, "null")) { > VLOG_WARN_ONCE("%s: The null interface type is deprecated and" > " may be removed in February 2013. Please email" > -- > 2.16.1 > > _______________________________________________ > dev mailing list > d...@openvswitch.org > https://mail.openvswitch.org/mailman/listinfo/ovs-dev
I was debugging why ofproto_class_find__() was so slow in the scale testing env, but not obvious slow down in a standalone setup when I just do repeat port creation/deletion. It seems to be caused by acquiring the dpif_mutex in dp_enumerate_types, but not sure what causes contention of that lock, and why it is not a problem in the standalone environment. This patch makes a lot more sense to me. And it should be even better than reverting the patch "ofproto: Include patch ports in mtu overriden check", because there was one call to ofproto_port_open_type() before that patch, and with this patch there is none. I suggest to update the commit message with new numbers from Ali's test. Also, I suggest to include the original discussion in commit message for more context to understand the impact: https://mail.openvswitch.org/pipermail/ovs-discuss/2018-February/046140.html Thanks, Han _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev