Cheap, tasty dishes to look for include laksa, Chinese-style mee sapi (beef noodle soup), red kolo mee (noodles with pork and a sweet barbecue sauce), tomato kueh tiaw (a fried rice-noodle dish) and shaved-ice desserts (ask for ‘ABC’ at stall 17). The Chinese seafood stalls that open in the afternoon are on the side facing the river.
From early morning until mid-afternoon there's also a stall selling fish-head-and-duck porridge, if that's your thing.
The market (which isn't, strictly speaking, open air) has two sections, separated by a road, on the site of a former fire station; the white tower was once used as a fire lookout.