As with all of your fiction, dialogue is helpful for breaking up action scenes. However, when adrenaline is flowing, people don't engage in lengthy discussions. To be realistic, keep dialogue short and snappy when writing action scenes. Looking again at The Spy Who Came in from the Cold, we have several examples: "He tugged sharply at the lower strand of wire and it came toward him, already cut. 'Come on,' he whispered urgently, 'start climbing.'" And a few paragraphs later: "He heard a voice in English from the Western side of the wall: 'Jump, Alec! Jump, man!' Now everyone was shouting, English, French and German mixed; he heard Smiley's voice from quite close: 'The girl, where's the girl?'"
Reading these last pages of the novel, dialogue occupies very little of the space, but it breaks up what would otherwise be long blocks of prose and helps propel the action. Note that the sentences in dialogue quotes are very short. People under stress use a minimum of words to get their point across. The fact that there's not time for more conveys a sense of urgency.
