pgbouncer logs and its efficiency

Dear Colleages,

I have two questions about pgbouncer logs, can you please share your
knowledge.

1. What is the meaning of those IDs in the log like
"S-0xaaaae460fcb0", "C-0xaaaae45d9fb0" ? I suspect that "S-" and "C-"
mean "server" and "client", but what are those HEX numbers?

2. How would you calculate the efficiency of pgbouncer, like
client_conns/server_conns ratio (current and average over over time)?

I have a case where pgbouncer is probably doing more bad than good,
but I would like to be able to prove or disprove it.

-- 
Victor Sudakov VAS4-RIPE
http://vas.tomsk.ru/
2:5005/49@fidonet