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Hardiness Zone: 8-9
Laurel from Port Orchard, WA
I'm not sure whether or not this falls under your definition of a cylinder-shaped privacy tree (it's more cone-shaped), but Thuja Green Giant cedars are probably the fastest growing evergreens out there. They grow at a rate of approximately 3-5 feet per year, and reach heights of 20 ft (when planted in rows) to 40 ft (if planted alone).
Another choice would be a Leyland cypress like Castlewellan. Known for its tendency toward conical growth, it has delicate lacy foliage and changes color for added winter interest. In the winter, the exterior of the tree turns gold while the interior remains green.
If you are looking for something that has more of a naturally shaped form, there are several great options in the conifer family. None of these trees will grow quite as fast, but they are also much longer-lived. Probably the fastest growing conifer is the Dawn Redwood. It tolerates a lot of standing water, and grows up to 6 ft per year.
In the pine tree department, White Pine, Longleaf Pine, Loblolly Pine, and Canary Island Pine are all said to be fast growing. These trees get quite large, however, so they cannot be planted close together. For more detailed information, browse these specific trees at the Arbor Foundation website: