Stop doing thousands of time checks each time we connect to a peer (#…

…3106)

* Stop checking the entire AddressBook for each connection attempt

* Stop redundant peer time checks within the address book

* Stop calling `Instant::now` 3 times for each address book update

* Only get the time once each time an address book method is called

* Update outdated comment

* Use an OrderedMap to efficiently store address book peers

* Add address book order tests

deny.toml

@@ -46,6 +46,10 @@ skip-tree = [
     # ticket #3063: redjubjub dependencies
     { name = "redjubjub", version = "=0.4.0" },
 
+    # ordered-map dependencies that should be dev-dependencies
+    # https://github.com/qwfy/ordered-map/pull/1
+    { name = "env_logger", version = "=0.7.1" },
+
     # ticket #2984: owo-colors dependencies
     { name = "color-eyre", version = "=0.5.11" },
 

zebra-chain/src/serialization/date_time.rs

@@ -1,14 +1,14 @@
 //! DateTime types with specific serialization invariants.
 
-use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
-use chrono::{TimeZone, Utc};
-
 use std::{
     convert::{TryFrom, TryInto},
     fmt,
     num::TryFromIntError,
 };
 
+use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
+use chrono::{TimeZone, Utc};
+
 use super::{SerializationError, ZcashDeserialize, ZcashSerialize};
 
 /// A date and time, represented by a 32-bit number of seconds since the UNIX epoch.
@@ -50,7 +50,7 @@ impl DateTime32 {
     ///
     /// If the number of seconds since the UNIX epoch is greater than `u32::MAX`.
     pub fn now() -> DateTime32 {
-        Utc::now()
+        chrono::Utc::now()
             .try_into()
             .expect("unexpected out of range chrono::DateTime")
     }
@@ -71,14 +71,18 @@ impl DateTime32 {
 
     /// Returns the duration elapsed since this time,
     /// or if this time is in the future, returns `None`.
-    pub fn checked_elapsed(&self) -> Option<Duration32> {
-        DateTime32::now().checked_duration_since(*self)
+    pub fn checked_elapsed(&self, now: chrono::DateTime<Utc>) -> Option<Duration32> {
+        DateTime32::try_from(now)
+            .expect("unexpected out of range chrono::DateTime")
+            .checked_duration_since(*self)
     }
 
     /// Returns the duration elapsed since this time,
     /// or if this time is in the future, returns zero.
-    pub fn saturating_elapsed(&self) -> Duration32 {
-        DateTime32::now().saturating_duration_since(*self)
+    pub fn saturating_elapsed(&self, now: chrono::DateTime<Utc>) -> Duration32 {
+        DateTime32::try_from(now)
+            .expect("unexpected out of range chrono::DateTime")
+            .saturating_duration_since(*self)
     }
 
     /// Returns the time that is `duration` after this time.

zebra-network/Cargo.toml

@@ -14,6 +14,7 @@ bytes = "1.1.0"
 chrono = "0.4"
 hex = "0.4"
 lazy_static = "1.4.0"
+ordered-map = "0.4.2"
 pin-project = "1.0.7"
 rand = "0.8"
 regex = "1"