Johnny Mathis’ first greatest-hits record came out in 1958. The 77-year-old is still at it. He’ll play the Palace Theatre tonight (Thursday, 8 PM, $36-$76). . . . O Brother, Where Art Thou? bluesman Chris Thomas King comes to the Linda tomorrow (Friday, 8 PM, $18, 465-5233). . . . “Dr. Dirty” John Valby is back at the Upstate Concert Hall on Firday along with Albany’s own foulmouthed jokesters Probing Digit (8 PM, $15, 371-0012). . . . After the Fall will celebrate the release of their new record Unkind at Valentine’s on Friday (9 PM, 432-6572). . . . The roving Behemoth Music Festival will be back in the Capital Region for a stop at Putnam Den on Friday featuring Total Slacker, U.S. Girls, Driftwood, Los Elk and Edith Pop (9 PM, $10, 584-8066). . . . Jamcrackers and John Kirk and Trish Miller will join forces on Friday at Universal Preservation Hall to benefit the Adirondack Great Camp Sagamore (8 PM, $15-$100, 315-354-5311). . . . Sensitive boy Alejandro Escovedo will play an acoustic set at Club Helsinki on Sunday (8 PM, $30, 828-4800). . . . Al DiMeola joins forces with Cuban pianist Gonzalo Rubalcaba at the Egg on Sunday (7:30 PM, $34.50, 437-1845).