From ed0752019f5d2a1ab418896b1e759cfade82124a Mon Sep 17 00:00:00 2001
From: Dave Smith <dsmith@thehive.com>
Date: Wed, 10 Dec 2008 18:18:05 -0700
Subject: [PATCH] Adding thrash test

---
 test/thrash_SUITE.erl | 99 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)
 create mode 100644 test/thrash_SUITE.erl

diff --git a/test/thrash_SUITE.erl b/test/thrash_SUITE.erl
new file mode 100644
index 0000000..b669cdb
--- /dev/null
+++ b/test/thrash_SUITE.erl
@@ -0,0 +1,99 @@
+%% -------------------------------------------------------------------
+%%
+%% bdberl: Port Driver Thrash tests
+%% Copyright (c) 2008 The Hive.  All rights reserved.
+%%
+%% -------------------------------------------------------------------
+-module(thrash_SUITE).
+
+-compile(export_all).
+
+all() ->
+    [test_thrash].
+
+-define(PROCS, 1).
+
+test_thrash(_Config) ->
+    %% Spin up 15 processes (async thread pool is 10)
+    start_procs(?PROCS),
+    wait_for_finish(?PROCS).
+
+start_procs(0) ->    
+    ok;
+start_procs(Count) ->
+    spawn_link(?MODULE, thrash_run, [self()]),
+    start_procs(Count-1).
+
+wait_for_finish(0) ->
+    ok;
+wait_for_finish(Count) ->
+    receive
+        {finished, Pid} ->
+            io:format("~p is done; ~p remaining.\n", [Pid, Count-1]),
+            wait_for_finish(Count-1)
+    end.
+
+thrash_run(Owner) ->
+    %% Seed the RNG
+    {A1, A2, A3} = now(),
+    random:seed(A1, A2, A3),
+
+    %% Open up a port and database
+    {ok, P} = bdberl_port:new(),
+    {ok, 0} = bdberl_port:open_database(P, "thrash", btree),
+
+    %% Start thrashing
+    thrash_incr_loop(P, Owner, 5000).
+
+
+
+thrash_incr_loop(Port, Owner, 0) ->
+    Owner ! {finished, self()};
+thrash_incr_loop(Port, Owner, Count) ->
+    %% Choose random key
+    Key = random:uniform(12),
+    
+    %% Start a txn that will read the current value of the key and increment by 1
+    F = fun() ->
+                case get_or_die(Port, 0, Key) of
+                    not_found ->
+                        Value = 0;
+
+                    {ok, Value} ->
+                        Value
+                end,
+                put_or_die(Port, 0, Key, Value)
+        end,
+    ok = do_txn(Port, F, 20),
+    thrash_incr_loop(Port, Owner, Count-1).
+
+
+get_or_die(Port, DbRef, Key) ->
+    case bdberl_port:get(Port, DbRef, Key) of
+        not_found ->
+            not_found;
+        {ok, Value} ->
+            Value
+    end.
+
+put_or_die(Port, DbRef, Key, Value) ->
+    ok = bdberl_port:put(Port, DbRef, Key, Value).
+
+do_txn(Port, F, 0) ->
+    ct:print("Max retries exceeded for txn; giving up!"),
+    failed;
+do_txn(Port, F, Count) ->
+    case bdberl_port:txn_begin(Port) of
+        ok ->
+            case catch(F()) of
+                {'EXIT', Reason} ->
+                    io:format("Txn failed; retrying. Last error: ~p\n", [Reason]),
+                    do_txn(Port, F, Count-1);
+                Other ->
+                    io:format("Txn success (~p): ~p\n", [Count, Other]),
+                    ok = bdberl_port:txn_commit(Port)
+            end;
+        {error, Reason} ->
+            io:format("Txn failed(2); retrying. Last error: ~p\n", [Reason]),
+            do_txn(Port, F, Count-1)
+    end.