From your description, you qualify for rent control, which means your landlord can only raise you rent at the rate of inflation (with certain exceptions).

From http://www.sftu.org/rentcontrol.html:

San Francisco's rent control law covers most rental property in San Francisco. If you live in San Francisco, you are covered by rent control unless you fall into one of these major exceptions

1. You live in a building constructed after June of 1979. This "new construction exemption" is the biggest exemption in SF

2. You live in subsidized housing, such as HUD housing projects.

3. You live in a dormitory, monastery, nunnery, etc.

4. You live in a residential hotel and have less than 28 days of continuous tenancy.