From 4747e380ecbe224f6d162a82449d69caa63ea8fe Mon Sep 17 00:00:00 2001
From: Roman Zeyde <me@romanzey.de>
Date: Tue, 22 May 2018 10:17:02 +0300
Subject: [PATCH] Update index once (instead at each status RPC)

---
 src/bin/indexrs.rs |  7 +++----
 src/mempool.rs     | 26 +++++++++++++++++---------
 src/query.rs       |  9 ++++-----
 3 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/src/bin/indexrs.rs b/src/bin/indexrs.rs
index dc647bd..a573ff2 100644
--- a/src/bin/indexrs.rs
+++ b/src/bin/indexrs.rs
@@ -83,15 +83,14 @@ fn run_server(config: &Config) {
     let query = query::Query::new(&store, &daemon, &index);
 
     crossbeam::scope(|scope| {
-        let poll_delay = Duration::from_secs(1);
+        let poll_delay = Duration::from_secs(5);
         scope.spawn(|| rpc::serve(config.rpc_addr(), &query));
         loop {
             thread::sleep(poll_delay);
             query.update_mempool().unwrap();
-            if tip == daemon.getbestblockhash().unwrap() {
-                continue;
+            if tip != daemon.getbestblockhash().unwrap() {
+                tip = index.update(&store, &daemon);
             }
-            tip = index.update(&store, &daemon);
         }
     });
 }
diff --git a/src/mempool.rs b/src/mempool.rs
index f723b38..e5b5886 100644
--- a/src/mempool.rs
+++ b/src/mempool.rs
@@ -21,11 +21,15 @@ struct MempoolStore {
 }
 
 impl MempoolStore {
-    pub fn new() -> MempoolStore {
+    fn new() -> MempoolStore {
         MempoolStore {
             map: RwLock::new(BTreeMap::new()),
         }
     }
+
+    fn clear(&self) {
+        self.map.write().unwrap().clear()
+    }
 }
 
 impl Store for MempoolStore {
@@ -69,12 +73,14 @@ impl Stats {
 
 pub struct Tracker {
     stats: HashMap<Sha256dHash, Stats>,
+    index: MempoolStore,
 }
 
 impl Tracker {
     pub fn new() -> Tracker {
         Tracker {
             stats: HashMap::new(),
+            index: MempoolStore::new(),
         }
     }
 
@@ -128,6 +134,14 @@ impl Tracker {
         for txid in old_txids.difference(&new_txids) {
             self.remove(txid);
         }
+
+        let mut rows = Vec::new();
+        for stats in self.stats.values() {
+            index_transaction(&stats.tx, 0, &mut rows)
+        }
+        self.index.clear();
+        self.index.persist(rows);
+
         debug!(
             "mempool update took {:.1} ms ({} txns)",
             t.elapsed().in_seconds() * 1e3,
@@ -144,14 +158,8 @@ impl Tracker {
         self.stats.remove(txid);
     }
 
-    pub fn build_index(&self) -> Box<Store> {
-        let mut rows = Vec::new();
-        for stats in self.stats.values() {
-            index_transaction(&stats.tx, 0, &mut rows)
-        }
-        let store = MempoolStore::new();
-        store.persist(rows);
-        Box::new(store)
+    pub fn index(&self) -> &Store {
+        &self.index
     }
 }
 
diff --git a/src/query.rs b/src/query.rs
index 7e3ede1..f63dfd3 100644
--- a/src/query.rs
+++ b/src/query.rs
@@ -213,17 +213,16 @@ impl<'a> Query<'a> {
     fn mempool_status(&self, script_hash: &[u8], confirmed_status: &Status) -> Status {
         let mut funding = vec![];
         let mut spending = vec![];
-        // TODO: build index once per Tracker::update()
-        let mempool_store = self.tracker.read().unwrap().build_index();
+        let tracker = self.tracker.read().unwrap();
         for t in self.load_txns(
-            &*mempool_store,
-            txids_by_script_hash(&*mempool_store, script_hash),
+            tracker.index(),
+            txids_by_script_hash(tracker.index(), script_hash),
         ) {
             funding.extend(self.find_funding_outputs(&t, script_hash));
         }
         // // TODO: dedup outputs (somehow) both confirmed and in mempool (e.g. reorg?)
         for funding_output in funding.iter().chain(confirmed_status.funding.iter()) {
-            if let Some(spent) = self.find_spending_input(&*mempool_store, &funding_output) {
+            if let Some(spent) = self.find_spending_input(tracker.index(), &funding_output) {
                 spending.push(spent);
             }
         }