Efficient way to save lots of small graphs with graph-tool

Question

Just wondering if anyone is aware of the most efficient way to do this. I have around 120k small graphs (<10 vertices). Loading the file through pickle is very slow. Two obvious solutions are:

1. Save one large graph and use property maps to index the individual graphs.
2. Save each graph as a separate .gt file.

There's a bit of overhead to implement either solution, so I wanted to reach out to the community first in case anyone had any insights.

Thanks in advance.