This was our bookgroup book for June and as has been happening, most of us thought it was a little light-weight.
The protagonist wakes up without knowing where he is and running into things that scare him. The dream he was having before he wakes up was a wonderful home, land, planet, but he's pretty sure it's not where he is. As he meets others, he finds out that's true. The ship was taking the seeds of humans to a planet, but there was a disaster and there's nowhere else to go. The ship keeps trying to make humans that will help, but many are killed because they're useless.
We meet other weird characters, but it's the protagonist who figures out all the good things that are possible in the ship until the end. A little depressing.