Eberle got his points in the first 7:38 of the game as all of the scoring was completed in the opening period.
The Oilers scored four goals in the first 12:24 on Canucks No. 1 goaltender Roberto Luongo, who struggled in his first exhibition appearance of the year.
Brendan Gaunce, with his second goal in two preseason games, scored for the Canucks.
Eberle opened the scoring 4:49 into the game as he slid a wraparound in off Luongo.
Then he made the first passes as Marincini and Perron scored on similar long shots 31 seconds apart to put the Oilers up 3-0 before the game was eight minutes old.
Joensuu scored Edmonton's final goal of the first period on a rebound after Luongo stretched across his crease to make a sensational save on Mark Arcobello's one timer.
Gaunce put the Canucks on the scoreboard just 42 seconds later as he shoveled the puck past Dubnyk, who made his second preseason appearance.