I have served twice, I think. If no one wanted to serve we wouldn't have much of a justice system.
One time on grand jury and I think that lasted a day. One time on petit jury for a rape/aggravated assault trial. I think the trial was a day, but it seemed like a month. Other years I have had to call in every day for a week to find out whether they needed me. They didn't.
I thought that it was painless. Grand jury was fascinating and the petit jury taught me a great deal about why the accused is so often found guilty, lack of evidence notwithstanding.