Purging of Log.NSF

One of my users regularly get a message on loading Notes indicating documents before a certain date (in this case 06/03/2003) should be purged from “database log.nsf”.

He goes on to select YES and it seems to run a very, very long time. Eventually, without any message on success or failure, it gives control back to the keyboard. Taking NO allows me to proceed normally.

Is this process normal? And if yes, how should we be able to know that it worked out fine?

Thanks.