Oil remained weak in Asia on Thursday after data showing record U.S. stockpiles sent prices tumbling to the lowest level in nearly six years in the previous session and analysts said a global glut would continue to keep the market under pressure. The U.S. Energy Information Administration (EIA) said domestic crude oil stocks rose by almost 9 million barrels last week to reach nearly 407 million, the highest level since the government began keeping records in 1982.