Fine-tune handling of GIL for search (#124)

src/document.rs

@@ -740,7 +740,7 @@ impl Document {
     {
         self.field_values
             .entry(field_name)
-            .or_insert_with(Vec::new)
+            .or_default()
             .push(Value::from(value));
     }
 

src/index.rs

@@ -308,19 +308,13 @@ impl Index {
         Ok(())
     }
 
-    /// Acquires a Searcher from the searcher pool.
+    /// Returns a searcher
     ///
-    /// If no searcher is available during the call, note that
-    /// this call will block until one is made available.
-    ///
-    /// Searcher are automatically released back into the pool when
-    /// they are dropped. If you observe this function to block forever
-    /// you probably should configure the Index to have a larger
-    /// searcher pool, or you are holding references to previous searcher
-    /// for ever.
-    fn searcher(&self, py: Python) -> Searcher {
+    /// This method should be called every single time a search query is performed.
+    /// The same searcher must be used for a given query, as it ensures the use of a consistent segment set.
+    fn searcher(&self) -> Searcher {
         Searcher {
-            inner: py.allow_threads(|| self.reader.searcher()),
+            inner: self.reader.searcher(),
         }
     }
 

src/searcher.rs

@@ -133,13 +133,14 @@ impl Searcher {
     #[pyo3(signature = (query, limit = 10, count = true, order_by_field = None, offset = 0))]
     fn search(
         &self,
-        _py: Python,
+        py: Python,
         query: &Query,
         limit: usize,
         count: bool,
         order_by_field: Option<&str>,
         offset: usize,
     ) -> PyResult<SearchResult> {
+        py.allow_threads(move || {
             let mut multicollector = MultiCollector::new();
 
             let count_handle = if count {
@@ -153,7 +154,8 @@ impl Searcher {
                     let collector = TopDocs::with_limit(limit)
                         .and_offset(offset)
                         .order_by_u64_field(order_by);
-                let top_docs_handle = multicollector.add_collector(collector);
+                    let top_docs_handle =
+                        multicollector.add_collector(collector);
                     let ret = self.inner.search(query.get(), &multicollector);
 
                     match ret {
@@ -167,11 +169,15 @@ impl Searcher {
                                 .collect();
                             (r, result)
                         }
-                    Err(e) => return Err(PyValueError::new_err(e.to_string())),
+                        Err(e) => {
+                            return Err(PyValueError::new_err(e.to_string()))
+                        }
                     }
                 } else {
-                let collector = TopDocs::with_limit(limit).and_offset(offset);
-                let top_docs_handle = multicollector.add_collector(collector);
+                    let collector =
+                        TopDocs::with_limit(limit).and_offset(offset);
+                    let top_docs_handle =
+                        multicollector.add_collector(collector);
                     let ret = self.inner.search(query.get(), &multicollector);
 
                     match ret {
@@ -185,7 +191,9 @@ impl Searcher {
                                 .collect();
                             (r, result)
                         }
-                    Err(e) => return Err(PyValueError::new_err(e.to_string())),
+                        Err(e) => {
+                            return Err(PyValueError::new_err(e.to_string()))
+                        }
                     }
                 }
             };
@@ -193,6 +201,7 @@ impl Searcher {
             let count = count_handle.map(|h| h.extract(&mut multifruit));
 
             Ok(SearchResult { hits, count })
+        })
     }
 
     /// Returns the overall number of documents in the index.