Constant FETCH_TIMEOUT_GRACE 

pub const FETCH_TIMEOUT_GRACE: Duration;

Grace period for a timed-out fetch: on the deadline processkit signals the process tree (terminate), waits this long for it to exit cleanly — flush, close the connection, drop any lock — then hard-kills. Only takes effect when a per-client timeout is set (Git::default_timeout / Jj::default_timeout); a fetch with no deadline is unaffected.