rosbag record pointcloud2 and tf data best practice?

edit

What is the best way to record pointcloud2 data? I tried rosbag record but the bag file becomes too large(2G) only for about 30 seconds. I tried -j to compress, but it cannot work with infinite buffer size(-b 0).

I tried: rosbag record -b 0 -O test.bag /tf /camera/rgb/points and rosbag record -b 0 -O test.bag -j /tf /camera/rgb/points

But both will exhaust all physical memory and throw a std::bad_alloc() exception then quit, so I have to limit the record to at most 80 seconds. Any option to drop down the frame rate or compress the pointcloud2 data into binary compressed .pcd files, but still maintain corresponding /tf data?