Long login times from command line when using credentials

[DSUser2000]

We are starting our sequences from AIX command line via dsjob under 7.5. Under Datastage 8.7 we now noticed that dsjob command seems to have a very large startup time (5s even for a simple -lprojects) and the dsjob process consumes a whole Power7 CPU core during this when used with user/password in its call parameters. When you don't specify user/password (so you circumvent the information server and call the engine directly if your user has those rights) that does not happen and dsjob works almost instantly.
We are asking ourselves if this is normal and if others are also experiencing this. In my eyes, this is a lot of wasted cpu power especially if you start many small sequences like this.