Prevent zero-latency mode from creating very large keyframes

[wreuven]

I am using zero-latency encoding.
In my test case, the encoder input does not change.

The first frame of first GOP was allocated about 20% of our 4mbps budget. This seems reasonable.

The first frame of the second GOP however is allocated 80%(!!) of our 4mbps budget. Even if the connection speed is double (8 mbps), this still means we've introduced a latency of 400 milli?

Is there some way to adjust this by configuration?

bandwidth 4000000 (4 mbps)
preset ultrafast
tune zerolatency
slices 4
x264opts no-mbtree:sliced-threads:sync-lookahead=0
gop_size 100
max_b_frames 0
refs 0