howto control the moving speed after pressing "alt-f7"?

[Zhengquan Z. m. l. <zha...@gm...>]

After pressing "alt-f7", I use the direction keys to move current window, but
I am not satisfied with the slow moving speed. I want to increase the moving
speed after pressing "alt-f7", I googled for an hour and checked the archived
mailing list and did not found anything relevant.

Can anybody give a hint?

Thanks.

Zhengquan