reset transaction after obtaining entries

CHANGELOG.md

@@ -2,6 +2,9 @@
 All notable changes to this project will be documented in this file. This change log follows the conventions of [keepachangelog.com](http://keepachangelog.com/).
 
 ## WIP
+## Fixed
+- Reset transaction after getting entries
+- Only use 24 reader slots
 
 ## 0.2.4
 ## Fixed

src/datalevin/constants.cljc

@@ -19,7 +19,7 @@
 
 (def ^:const +max-dbs+          128)
 (def ^:const +max-readers+      126)
-(def ^:const +use-readers+      64)    ; leave the rest to others
+(def ^:const +use-readers+      24)    ; leave the rest to others
 (def ^:const +init-db-size+     100)   ; in megabytes
 (def ^:const +default-val-size+ 16384) ; in bytes
 (def ^:const +max-key-size+     511)   ; in bytes

src/datalevin/lmdb.clj

@@ -559,9 +559,13 @@
   (entries [this dbi-name]
     (assert (not (closed? this)) "LMDB env is closed.")
     (let [^DBI dbi   (get-dbi this dbi-name)
-          ^Rtx rtx   (get-rtx pool)
-          ^Stat stat (.stat ^Dbi (.-db dbi) (.-txn rtx))]
-      (.-entries stat)))
+          ^Rtx rtx   (get-rtx pool)]
+      (try
+        (.-entries ^Stat (.stat ^Dbi (.-db dbi) (.-txn rtx)))
+        (catch Exception e
+          (raise "Fail to get entries: " (ex-message e)
+                 {:dbi dbi-name}))
+        (finally (reset rtx)))))
 
   (transact [this txs]
     (assert (not (closed? this)) "LMDB env is closed.")

test/datalevin/lmdb_test.clj

@@ -45,6 +45,10 @@
                    [:put "b" :long 1 :data :long]
                    [:put "b" 2 3 :long :long]]))
 
+  (testing "entries"
+    (is (= 6 (sut/entries lmdb "a")))
+    (is (= 9 (sut/entries lmdb "b"))))
+
   (testing "get-value"
     (is (= 2 (sut/get-value lmdb "a" 1)))
     (is (= [1 2] (sut/get-value lmdb "a" 1 :data :data false)))
@@ -71,6 +75,10 @@
                         [:del "a" :non-exist]])
     (is (nil? (sut/get-value lmdb "a" 1))))
 
+  (testing "entries-again"
+    (is (= 5 (sut/entries lmdb "a")))
+    (is (= 9 (sut/entries lmdb "b"))))
+
   (testing "non-existent dbi"
     (is (thrown-with-msg? Exception #"open-dbi" (sut/get-value lmdb "z" 1))))