issue: how to set max_new_tokens ?

[Dada-Cloudzxy]

how to set max_new_tokens? I just could find 'maxlen' var in 'main.py', and it would cost too muck time for testing.

[Dada-Cloudzxy]

When I set maxlen to 512, my tests on the HH dataset took about 30 times longer than the baseline method.

[Dada-Cloudzxy]

That doesn't seem to match what the paper says

[Dada-Cloudzxy]

@hongyanz @Liyuhui-12