From 8bad411962dbb234f8a3ce0bc04fe44e58e88f66 Mon Sep 17 00:00:00 2001
From: anatoly yakovenko <anatoly@solana.com>
Date: Tue, 17 Jul 2018 15:26:10 -0700
Subject: [PATCH] env variable for default metrics rate that gets set for
 counters (#670)

* env variable for default metrics rate that gets set for counters

* ignore if env rate is set to 0

* use a slow rate by default

* fixed test
---
 src/counter.rs | 66 ++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 56 insertions(+), 10 deletions(-)

diff --git a/src/counter.rs b/src/counter.rs
index afdac25a3a..7a84e73cdd 100644
--- a/src/counter.rs
+++ b/src/counter.rs
@@ -1,9 +1,10 @@
 use influx_db_client as influxdb;
 use metrics;
+use std::env;
 use std::sync::atomic::{AtomicUsize, Ordering};
 use timing;
 
-const INFLUX_RATE: usize = 100;
+const DEFAULT_METRICS_RATE: usize = 100;
 
 pub struct Counter {
     pub name: &'static str,
@@ -12,7 +13,7 @@ pub struct Counter {
     pub times: AtomicUsize,
     /// last accumulated value logged
     pub lastlog: AtomicUsize,
-    pub lograte: usize,
+    pub lograte: AtomicUsize,
 }
 
 macro_rules! create_counter {
@@ -22,7 +23,7 @@ macro_rules! create_counter {
             counts: AtomicUsize::new(0),
             times: AtomicUsize::new(0),
             lastlog: AtomicUsize::new(0),
-            lograte: $lograte,
+            lograte: AtomicUsize::new($lograte),
         }
     };
 }
@@ -35,7 +36,7 @@ macro_rules! inc_counter {
 
 macro_rules! inc_new_counter {
     ($name:expr, $count:expr) => {{
-        static mut INC_NEW_COUNTER: Counter = create_counter!($name, 10);
+        static mut INC_NEW_COUNTER: Counter = create_counter!($name, 0);
         inc_counter!(INC_NEW_COUNTER, $count);
     }};
     ($name:expr, $count:expr, $lograte:expr) => {{
@@ -45,11 +46,26 @@ macro_rules! inc_new_counter {
 }
 
 impl Counter {
+    fn default_log_rate() -> usize {
+        let v = env::var("SOLANA_DEFAULT_METRICS_RATE")
+            .map(|x| x.parse().unwrap_or(DEFAULT_METRICS_RATE))
+            .unwrap_or(DEFAULT_METRICS_RATE);
+        if v == 0 {
+            DEFAULT_METRICS_RATE
+        } else {
+            v
+        }
+    }
     pub fn inc(&mut self, events: usize) {
         let counts = self.counts.fetch_add(events, Ordering::Relaxed);
         let times = self.times.fetch_add(1, Ordering::Relaxed);
-        let lastlog = self.lastlog.load(Ordering::Relaxed);
-        if times % self.lograte == 0 && times > 0 {
+        let mut lograte = self.lograte.load(Ordering::Relaxed);
+        if lograte == 0 {
+            lograte = Counter::default_log_rate();
+            self.lograte.store(lograte, Ordering::Relaxed);
+        }
+        if times % lograte == 0 && times > 0 {
+            let lastlog = self.lastlog.load(Ordering::Relaxed);
             info!(
                 "COUNTER:{{\"name\": \"{}\", \"counts\": {}, \"samples\": {},  \"now\": {}}}",
                 self.name,
@@ -57,8 +73,6 @@ impl Counter {
                 times,
                 timing::timestamp(),
             );
-        }
-        if times % INFLUX_RATE == 0 && times > 0 {
             metrics::submit(
                 influxdb::Point::new(&format!("counter-{}", self.name))
                     .add_field(
@@ -74,7 +88,8 @@ impl Counter {
 }
 #[cfg(test)]
 mod tests {
-    use counter::Counter;
+    use counter::{Counter, DEFAULT_METRICS_RATE};
+    use std::env;
     use std::sync::atomic::{AtomicUsize, Ordering};
     #[test]
     fn test_counter() {
@@ -84,7 +99,7 @@ mod tests {
         unsafe {
             assert_eq!(COUNTER.counts.load(Ordering::Relaxed), 1);
             assert_eq!(COUNTER.times.load(Ordering::Relaxed), 1);
-            assert_eq!(COUNTER.lograte, 100);
+            assert_eq!(COUNTER.lograte.load(Ordering::Relaxed), 100);
             assert_eq!(COUNTER.lastlog.load(Ordering::Relaxed), 0);
             assert_eq!(COUNTER.name, "test");
         }
@@ -106,4 +121,35 @@ mod tests {
         inc_new_counter!("counter-1", 1);
         inc_new_counter!("counter-2", 1, 2);
     }
+    #[test]
+    fn test_lograte() {
+        static mut COUNTER: Counter = create_counter!("test_lograte", 0);
+        inc_counter!(COUNTER, 2);
+        unsafe {
+            assert_eq!(
+                COUNTER.lograte.load(Ordering::Relaxed),
+                DEFAULT_METRICS_RATE
+            );
+        }
+    }
+    #[test]
+    fn test_lograte_env() {
+        assert_ne!(DEFAULT_METRICS_RATE, 0);
+        static mut COUNTER: Counter = create_counter!("test_lograte_env", 0);
+        env::set_var("SOLANA_DEFAULT_METRICS_RATE", "50");
+        inc_counter!(COUNTER, 2);
+        unsafe {
+            assert_eq!(COUNTER.lograte.load(Ordering::Relaxed), 50);
+        }
+
+        static mut COUNTER2: Counter = create_counter!("test_lograte_env", 0);
+        env::set_var("SOLANA_DEFAULT_METRICS_RATE", "0");
+        inc_counter!(COUNTER2, 2);
+        unsafe {
+            assert_eq!(
+                COUNTER2.lograte.load(Ordering::Relaxed),
+                DEFAULT_METRICS_RATE
+            );
+        }
+    }
 }