I wash my large knives by hand, with a soapy sponge.
Always keep the blade pointed away from you.
I do not recommend putting large knives in the dishwasher . Small paring knives , with the point down, are fine in the dishwasher, as long as they don’t have a wooden handle. (Wooden handles and dishwashers don’t mix.)
Large knives in the dishwasher are an accident waiting to happen. They could nick or chip dishes and glassware as well as the dishwashing rack itself. (Once the dishwasher rack gets nicked it may well start to rust. Those racks are REALLY expensive to replace.)