system slows after bootup for some time

Hi,
I am using a Linux system running at run level 3. I am finding a wired problem, once the system boots, the system terminal slows down, I need to type the characters repeatedly to enter my login and password info. Also running any commands takes time, it stays in this condition for some time and then behaves normally.

But when I ssh into this system (soon after it boots) from other systems the system behavior is normal.

My first guess was that the system is overloaded by some process but everything seems to be fine. Can someone guide me to find out this behavior .

thanks
joy

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