What pitcher holds the record for most strikeouts lifetime?

Tom Cheney of the Washington Senators holds the MLB record for most strikeouts in a single game when he struckout 21 Baltimore Orioles batters in a 16 inning game in 1962. Kerry Wood, Randy Johnson, and Roger Clemens (twice) hold the MLB record for most strikeouts in a 9 inning game with 20. == ==