We’re deep into the golden age of the classic-rock memoir. Increasingly, everyone wants to issue the bookstore equivalent of a double album.

These autobiographies have become shaggy monsters. Elvis Costello’s was a Tolstoyan 674 pages. Those from Keith Richards (564 pages), Bruce Springsteen (510 pages) and Mike Love (436 pages) also were wide loads, all-you-can-eat visits to the word buffet. The arms race is on, and rock’s more inflated figures have yet to weigh in. Will Roger Waters’ autobiography be a 54-volume set? Roadies in druid outfits could peddle it door to door.

Robbie Robertson’s memoir, “Testimony,” coasts in at size XL, an even 500 pages. It once existed in vastly longer form, he writes in his acknowledgments. He thanks an acquaintance who read the early, uncut version and “never flinched.”

“Testimony” covers only the first 33 years of Robertson’s life. It ends in 1976, as the Band — he was its lead guitarist and principal songwriter — performs its farewell concert, filmed by Martin Scorsese and released as “The Last Waltz” in 1978.

It’s a smart place to stop. By 1976 the Band had lost cabin pressure — oxygen masks had dropped — while cruising at 30,000 feet. Drug use had taken a toll. Bristling egos clashed. Internecine warfare erupted over money.

After “The Last Waltz” the gloves really came off. Robertson got the worst of it. Drummer Levon Helm wrote a memoir called “This Wheel’s on Fire” (1993) in which he bitterly accused Robertson of taking songwriting credits that didn’t belong to him and seizing authoritarian control of what had been a famously democratic band of musicians.

That had to sting. But where Helm went low, Robertson has chosen to go high. His memories of Helm, who died in 2012, are mostly sunny and often hilarious. It’s hard to write a bad sentence that begins, as one about a brewing fistfight does, with the words “Levon put his corn dog down.”

Robertson, now 73, blames the bad feelings on paranoia brought on by Helm’s serious drug use. “It was like some demon had crawled into my friend’s soul and pushed a crazy, angry button.” Helm might have also possessed, he writes, “a country-boy inferiority complex.”

Playing with Dylan

“Testimony” ends when its author was still relatively young, but it is packed with incident. By this time Robertson had played on Bob Dylan’s “going electric” tours of 1965 and 1966; helped make “The Basement Tapes” in and around Woodstock, N.Y., with Dylan and members of what would become the Band; and written indelible songs like “The Weight” and “The Night They Drove Old Dixie Down.”

His memoir is confident and well oiled. At times it has the mythic sweep of an early Terrence Malick movie. It makes a kind of sense that “Testimony” moves in bursts, like a screenplay. Robertson says he wrote his best songs for the Band after he began studying the screenplays he bought at the fabled (and now shuttered) Gotham Book Mart in New York.

Robertson grew up in Toronto. His mother had been born on the Six Nations Indian Reserve in southwestern Ontario; later in life he discovered that his father, whom he never met, had been a card shark and also Jewish. About this dual heritage, he reports, “You could say I’m an expert when it comes to persecution.”

Dylan blows into this memoir like a blazing tumbleweed. He puffed on cigarettes harder than Bette Davis did, Robertson writes, and banged out songs on his typewriter at lightning speed. His portrait of Dylan is warm and complex. When Dylan got married for the first time, to Sara Lownds, he asked Robertson to come along as a witness. “You mean a best man at your wedding?” Robertson asked.

Dylan replied, “Well, I don’t know about ‘best man.’ That’s quite a commitment. Maybe ‘good man’ or ‘very good man.’ How would that be?”

Weed and women

Drugs and sex are a constant IV drip in this memoir. Pot is smoked with John Lennon. Liaisons with Carly Simon and Edie Sedgwick are recounted. A visit from Allen Ginsberg is hilariously ducked.

The Band’s first two albums, “Music From Big Pink” (1968) and “The Band” (1969), sounded antiquated and thrillingly modern at the same time; they seemed to open new vistas on American life. The vocals were passed from man to man as if they were a spliff.

This egalitarian quality made the group seem unlike any popular rock band. “We were holding a different hand — like five-card stud,” Robertson writes. “Nothing wild. Everything faceup.”

Everyone in the Band became famous and wealthy. The bad habits and car crashes commenced. “Oh, you don’t know the shape I’m in,” keyboard player Richard Manuel sang in one of Robertson’s best-known songs. He was speaking as if for all of them.

© 2016 The New York Times Company