[bench/client] fix remote_cmds for multiple clients

bench/client.py

@@ -130,10 +130,11 @@ def run_remote_clients(cmd: str, out: Path, err: Path, csv: Path,
 
         files.extend([h_out, h_err, h_csv])
 
+        r_cmd = remote_cmd.format(host=host)
         h_cmd = cmd.format(outfile=h_csv)
 
-        clients.append(
-            Client(h_cmd, h_out, h_err, remote_cmd=remote_cmd, host=host))
+        clients.append(Client(h_cmd, h_out, h_err, remote_cmd=r_cmd,
+                              host=host))
 
     # await all clients
     for client in clients:

eval.py

@@ -118,11 +118,11 @@ def bench(server_cmds) -> EvalResult:
                 'SERVER': server_name
             }
 
-            remote_cmd = None
-            if REMOTE_CMD:
-                remote_cmd = REMOTE_CMD.format(host=HOST, ssh_port=SSH_PORT)
+            remote_cmd = None if not REMOTE_CMD else REMOTE_CMD.format(
+                host='{host}', ssh_port=SSH_PORT)
+            if remote_cmd:
                 # make sure the benchdir is available on the HOST
-                remote_prepare_cmd = f'{remote_cmd} mkdir -p {bench_dir}'
+                remote_prepare_cmd = f'{remote_cmd.format(host=HOST)} mkdir -p {bench_dir}'
                 cmd_run(remote_prepare_cmd, log)
 
             measure_cmd = MEASURE_CMD.format(**substitutions)