Hello, On Fri, 20 Aug 2021, Dust Li wrote: > estimation_timer will iterate the est_list to do estimation > for each ipvs stats. When there are lots of services, the > list can be very large. > We found that estimation_timer() run for more then 200ms on a > machine with 104 CPU and 50K services. > > yunhong-cgl jiang report the same phenomenon before: > https://www.spinics.net/lists/lvs-devel/msg05426.html > > In some cases(for example a large K8S cluster with many ipvs services), > ipvs estimation may not be needed. So adding a sysctl blob to allow > users to disable this completely. > > Default is: 1 (enable) > > Cc: yunhong-cgl jiang <xintian1976@xxxxxxxxx> > Signed-off-by: Dust Li <dust.li@xxxxxxxxxxxxxxxxx> Looks good to me, thanks! Acked-by: Julian Anastasov <ja@xxxxxx> > --- > v2: Use common sysctl facilities > v3: Fix sysctl_run_estimation() redefine when CONFIG_SYSCTL not enabled > v4: Some typo and minor fixes > > Documentation/networking/ipvs-sysctl.rst | 11 +++++++++++ > include/net/ip_vs.h | 11 +++++++++++ > net/netfilter/ipvs/ip_vs_ctl.c | 8 ++++++++ > net/netfilter/ipvs/ip_vs_est.c | 5 +++++ > 4 files changed, 35 insertions(+) > > diff --git a/Documentation/networking/ipvs-sysctl.rst b/Documentation/networking/ipvs-sysctl.rst > index 2afccc63856e..95ef56d62077 100644 > --- a/Documentation/networking/ipvs-sysctl.rst > +++ b/Documentation/networking/ipvs-sysctl.rst > @@ -300,3 +300,14 @@ sync_version - INTEGER > > Kernels with this sync_version entry are able to receive messages > of both version 1 and version 2 of the synchronisation protocol. > + > +run_estimation - BOOLEAN > + 0 - disabled > + not 0 - enabled (default) > + > + If disabled, the estimation will be stop, and you can't see > + any update on speed estimation data. > + > + You can always re-enable estimation by setting this value to 1. > + But be careful, the first estimation after re-enable is not > + accurate. > diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h > index 7cb5a1aace40..ff1804a0c469 100644 > --- a/include/net/ip_vs.h > +++ b/include/net/ip_vs.h > @@ -931,6 +931,7 @@ struct netns_ipvs { > int sysctl_conn_reuse_mode; > int sysctl_schedule_icmp; > int sysctl_ignore_tunneled; > + int sysctl_run_estimation; > > /* ip_vs_lblc */ > int sysctl_lblc_expiration; > @@ -1071,6 +1072,11 @@ static inline int sysctl_cache_bypass(struct netns_ipvs *ipvs) > return ipvs->sysctl_cache_bypass; > } > > +static inline int sysctl_run_estimation(struct netns_ipvs *ipvs) > +{ > + return ipvs->sysctl_run_estimation; > +} > + > #else > > static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs) > @@ -1163,6 +1169,11 @@ static inline int sysctl_cache_bypass(struct netns_ipvs *ipvs) > return 0; > } > > +static inline int sysctl_run_estimation(struct netns_ipvs *ipvs) > +{ > + return 1; > +} > + > #endif > > /* IPVS core functions > diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c > index c25097092a06..cbea5a68afb5 100644 > --- a/net/netfilter/ipvs/ip_vs_ctl.c > +++ b/net/netfilter/ipvs/ip_vs_ctl.c > @@ -2017,6 +2017,12 @@ static struct ctl_table vs_vars[] = { > .mode = 0644, > .proc_handler = proc_dointvec, > }, > + { > + .procname = "run_estimation", > + .maxlen = sizeof(int), > + .mode = 0644, > + .proc_handler = proc_dointvec, > + }, > #ifdef CONFIG_IP_VS_DEBUG > { > .procname = "debug_level", > @@ -4090,6 +4096,8 @@ static int __net_init ip_vs_control_net_init_sysctl(struct netns_ipvs *ipvs) > tbl[idx++].data = &ipvs->sysctl_conn_reuse_mode; > tbl[idx++].data = &ipvs->sysctl_schedule_icmp; > tbl[idx++].data = &ipvs->sysctl_ignore_tunneled; > + ipvs->sysctl_run_estimation = 1; > + tbl[idx++].data = &ipvs->sysctl_run_estimation; > > ipvs->sysctl_hdr = register_net_sysctl(net, "net/ipv4/vs", tbl); > if (ipvs->sysctl_hdr == NULL) { > diff --git a/net/netfilter/ipvs/ip_vs_est.c b/net/netfilter/ipvs/ip_vs_est.c > index 05b8112ffb37..9a1a7af6a186 100644 > --- a/net/netfilter/ipvs/ip_vs_est.c > +++ b/net/netfilter/ipvs/ip_vs_est.c > @@ -100,6 +100,9 @@ static void estimation_timer(struct timer_list *t) > u64 rate; > struct netns_ipvs *ipvs = from_timer(ipvs, t, est_timer); > > + if (!sysctl_run_estimation(ipvs)) > + goto skip; > + > spin_lock(&ipvs->est_lock); > list_for_each_entry(e, &ipvs->est_list, list) { > s = container_of(e, struct ip_vs_stats, est); > @@ -131,6 +134,8 @@ static void estimation_timer(struct timer_list *t) > spin_unlock(&s->lock); > } > spin_unlock(&ipvs->est_lock); > + > +skip: > mod_timer(&ipvs->est_timer, jiffies + 2*HZ); > } > > -- > 2.19.1.3.ge56e4f7 > > > Regards -- Julian Anastasov <ja@xxxxxx>
