diff --git a/README.adoc b/README.adoc
index 6892b54..96ffdb4 100644
--- a/README.adoc
+++ b/README.adoc
@@ -1145,6 +1145,8 @@ less out/aarch64/gem5/default/0/termout.txt
 less out/aarch64/gem5/default/1/termout.txt
 ....
 
+Each line is prepended with the timestamp in seconds since the start of the program when it appeared.
+
 You can also add a prefix to the build ID before a period:
 
 ....
diff --git a/configure b/configure
index 6d4b6b3..ace578e 100755
--- a/configure
+++ b/configure
@@ -34,6 +34,7 @@ coreutils \
 cpio \
 expect \
 git \
+moreutils \
 tmux \
 unzip \
 vinagre \
diff --git a/gem5/gem5 b/gem5/gem5
index 60600f0..ff52563 160000
--- a/gem5/gem5
+++ b/gem5/gem5
@@ -1 +1 @@
-Subproject commit 60600f09c25255b3c8f72da7fb49100e2682093a
+Subproject commit ff52563a214c71fcd1e21e9f00ad839612032e3b
diff --git a/run b/run
index 8c7c571..244d8e3 100755
--- a/run
+++ b/run
@@ -363,7 +363,7 @@ if "$tmux"; then
     eval "./tmu ./rungdb -a '${arch} -L ${common_linux_variant}' -n ${common_run_id} ${tmux_args}"
   fi
 fi
-cmd="${cmd} \\
-|& tee ${common_termout_file} \
+cmd="time ${cmd} \\
+|& tee >(ts -s %.s > ${common_termout_file}) \
 "
 "${root_dir}/eeval" "$cmd" "${common_run_dir}/run.sh"