diff --git a/site-modules/profile/templates/swh/deploy/graph/swh-graph-shm-mount.service.erb b/site-modules/profile/templates/swh/deploy/graph/swh-graph-shm-mount.service.erb
index 79dbb307..9b911af6 100644
--- a/site-modules/profile/templates/swh/deploy/graph/swh-graph-shm-mount.service.erb
+++ b/site-modules/profile/templates/swh/deploy/graph/swh-graph-shm-mount.service.erb
@@ -1,22 +1,23 @@
 # Managed by puppet class profile::swh::deploy::graph
 # Changes will be overwritten
 
 [Unit]
 Description=swh-graph RAM data cache in /dev/shm
 
 [Service]
 Type=simple
 User=<%= @user %>
 Group=<%= @group %>
 ExecStartPre=sh -c "[ -d <%= @shm_path %> ] || mkdir -p <%= @shm_path %>"
 ExecStartPre=sh -c "[ -L <%= @shm_path %>/graph.stats ] || ln -sf <%= @compressed_graph_path %>/* <%= @shm_path %>"
 <% @files_to_copy_to_shm.each do |file| -%>
-ExecStartPre=sh -c "[ -f <%= @shm_path %>/<%= file %> ] || cp --remove-destination <%= @compressed_graph_path %>/<%= file %> <%= @shm_path %>"
+ExecStartPre=sh -c "if [ -L <%= @shm_path %>/<%= file %> ] || ! [ -f <%= @shm_path %>/<%= file %> ]; then cp --remove-destination <%= @compressed_graph_path %>/<%= file %> <%= @shm_path %>/; fi"
 <% end -%>
 ExecStart=sh -c "set -e; while [ -f <%= @shm_path %>/graph.graph ]; do sleep 1; done; exit 1"
 
+TimeoutStartSec=1h
 Restart=on-failure
 RestartSec=5
 
 [Install]
 WantedBy=multi-user.target