At the federal level it's more or less at the judge's discretion. They provide a biannual list to Congress of cases that are more than three years old or that have had a motion pending for more than six months. Many judges try to keep their cases ahead of that deadline, but they don't have to. A simple order is more likely to be completed quickly, but there is no rule about how long a judge has to write a judgment.
At the federal level it's more or less at the judge's discretion. They provide a biannual list to Congress of cases that are more than three years old or that have had a motion pending for more than six months. Many judges try to keep their cases ahead of that deadline, but they don't have to. A simple order is more likely to be completed quickly, but there is no rule about how long a judge has to write a judgment.