diff --git a/.gitignore b/.gitignore
index 3bff7eb..a71e181 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,3 +16,4 @@ _build/
 /emqtt_bench
 libquicer_nif.so
 rebar3
+*.crashdump
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8770c6c..30bc4d7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,21 +1,31 @@
+# emqtt-bench changelog
 
-0.4 (2019-07-29)
-----------------
+## 0.4.5
+
+* Default value for `--inflight` option is changed from `0` (no back-pressure) to `1`.
+  i.e. `max-inflight` is `1` by default for QoS 1 and 2 messages.
+
+## 0.4.4
+
+Main changes comparing to 0.4.0
+
+* Release on otp 24.2.1
+* Multiple source IP address support (to get around the 64K source port limit)
+* Reports publisher overrun for QoS 1 (when the ack is received after the interval set by `--interval_of_msg` option)
+
+## 0.4 (2019-07-29)
 
 Use the new Erlang MQTT v5.0 client
 
-0.3 (2016-01-29)
-----------------
+## 0.3 (2016-01-29)
 
 emqtt_bench_sub: support to subscribe mutiple topics (#9)
 
-0.2 (2015-10-08)
-----------------
+## 0.2 (2015-10-08)
 
 emqtt_bench_pub, emqtt_bench_sub scripts
 
-0.1 (2015-04-23)
-----------------
+## 0.1 (2015-04-23)
 
 first public release
 
diff --git a/src/emqtt_bench.erl b/src/emqtt_bench.erl
index 76a9d8f..1158407 100644
--- a/src/emqtt_bench.erl
+++ b/src/emqtt_bench.erl
@@ -82,7 +82,7 @@
          {shortids, $s, "shortids", {boolean, false},
           "use short ids for client ids"},
          {lowmem, $l, "lowmem", boolean, "enable low mem mode, but use more CPU"},
-         {inflight, $F,"inflight", {integer, 0},
+         {inflight, $F,"inflight", {integer, 1},
           "maximum inflight messages for QoS 1 an 2, value 0 for 'infinity'"}
         ]).