Performance of Greedy vs. Lazy Regex Quantifiers

A common misconception about regular expression performance is that lazy quantifiers (also called non-greedy, reluctant, minimal, or ungreedy) are faster than their greedy equivalents. This is generally not true, but with an important qualifier: in practice, lazy quantifiers often are faster. This seeming contradiction is due to the fact that many people rely on backtracking to compensate for the impreciseness of their patterns, often without realizing this is what they're doing.

Hence, the previously mentioned misconception stems from that fact that lazy quantifiers often result in much less backtracking when combined with long subject strings and the (mis)use of overly flexible regex tokens such as the dot.