For years, it was a schedule as predictable as a calendar: Novelists who specialized in mysteries, thrillers and romance would write one book a year, output that was considered not only sufficient, but productive.

But the e-book age has accelerated the metabolism of book publishing. Authors are now pulling the literary equivalent of a double shift, churning out short stories, novellas or even an extra full-length book each year.

They are trying to satisfy impatient readers who have become used to downloading any e-book they want at the touch of a button, and the publishers who are nudging them toward greater productivity in the belief that the more their authors’ names are out in public, the bigger stars they will become.

“It used to be that once a year was a big deal,” said Lisa Scottoline, a best-selling author of thrillers. “You could saturate the market. But today the culture is a great big hungry maw, and you have to feed it.”

The push for more material comes as publishers and booksellers are desperately looking for ways to hold onto readers being lured by other forms of entertainment, much of it available nonstop and almost instantaneously. Television shows are rushed online only hours after they are originally broadcast, and some movies are offered on demand at home before they have left theaters. In this environment, publishers say, producing one book a year, and nothing else, is just not enough.

At the same time, the Internet has allowed readers to enjoy a more intimate relationship with their favorite authors, whom they now expect to be accessible online via blogs, Q and A’s on Twitter and updates on Facebook.

Some of the extra work is being pushed by authors themselves, who are easing their own fears that if they stay out of the fickle book market too long, they might be forgotten.

Scottoline has increased her output from one book a year to two, which she accomplishes with a brutal writing schedule: 2,000 words a day, seven days a week, usually “starting at 9 a.m. and going until Colbert,” she said.

The British thriller writer Lee Child, who created the indelible character Jack Reacher, is now supplementing his hardcover books with short stories that are published in digital-only format, an increasingly popular strategy to drum up attention for the coming publication of a novel.

Child’s first story, a 40-page exploration of Reacher as a teenager, was released last August, several weeks before his latest novel came out in print. On the advice of his publisher, he is planning to write another digital-only short story this summer.

“Everybody’s doing a little more,” said Child, who is published by Delacorte Press, part of Random House. “It seems like we’re all running faster to stay in the same place.”

Even John Grisham is working overtime. Grisham, who used to write one book each year, now does an additional series aimed at middle-grade readers, the popular “Theodore Boone” novels that are published annually.

Publishers say that a carefully released short story, timed six to eight weeks before a big hardcover comes out, can entice new readers who might be willing to pay 99 cents for a story but reluctant to spend $14 for a new e-book or $26 for a hardcover.

That can translate into higher preorder sales for the novel and even a lift in sales of older books by the author, which are easily accessible as e-book impulse purchases for consumers with Nooks or Kindles.

Jennifer Enderlin, the associate publisher of St. Martin’s Paperbacks, said the strategy had worked for many of her authors, who saw a big uptick in hardcover sales, book over book, once they started releasing more work.

“I almost feel sorry for authors these days with how much publishers are asking of them,” Enderlin said. “We always say, ‘How about a little novella that we can sell for 99 cents?”’

That has replaced a carefully plotted print publication system, when readers waited eagerly for the yearly release of a favorite author’s novel. At that rate, publishers reasoned, readers would never be overwhelmed by content.

Today’s readers seem incapable of being overwhelmed.

Scott Schiefelbein, a lawyer in Portland, Ore., wrote an enthusiastic review last month on Amazon.com of “Second Son,” a short story by Child that Schiefelbein read after buying his latest novel, “The Affair,” for his Kindle.

There is “no limit” to the number of Child’s books he would buy, Schiefelbein said.

“I’ll give basically anything he writes a chance,” he said. “With my favorite authors, I always want to read more from them.”

Some of the biggest authors have become so productive that they are nearly an impossible act to follow. Airport bookstores these days can feature not just one stack of James Patterson books, but by an entire rack of them, sometimes more than six titles at a time. Patterson produced 12 books last year, aided on some titles by co-writers. He will publish 13 this year.

“A lot of publishers and authors have looked at what James Patterson is doing and realized, ‘I may not be able to publish nine books a year, but certainly I can do two,”’ said Brian Tart, the publisher of Dutton, an imprint of Penguin. “They were able to grow him and grow the readership using that strategy.”

(The new expectations do not apply to literary novelists like Jeffrey Eugenides and Jonathan Franzen, who can publish a new novel approximately every decade and still count on plenty of high-profile book reviews to promote it.)

Publishers also believe that Salinger-like reclusiveness, which once created an aura of intrigue around an author, is not a viable option in the age of interconnectivity.

“Particularly now with social media, authors are constantly in contact with their fans in a way that they never were before,” said Liate Stehlik, the publisher of William Morrow, Avon and Voyager, imprints of HarperCollins. “Now it seems to make more sense to have your author out in the media consciousness as much as you can.”

Authors don’t seem to be writing digital-only short stories for the money. Advances are typically not part of the bargain, and the works are priced so low (usually $0.99 or $1.99) that they don’t produce much revenue, even if they take several weeks or months to write.

But some authors said that even though they are beginning to accept them as one of the necessary requirements of book marketing, they still find them taxing to produce.

“I have been known to be a little grumpy on the subject sometimes,” said Steve Berry, a popular thriller writer who writes short stories that are released between books. “It does sap away some of your energy. You don’t ever want to get into a situation where your worth is being judged by the amount of your productivity.”

© 2012 The New York Times Company