Today I end up killing pgadmin a few times while inadvertantly running some huge queries and some ALTER requests that were blocked due to the queries. I should have canceled the queries from pgadmin, but I didn't. When I saw that the postgres processes were using up 100% of the CPU, I looked up the process id's of the ALTERs and runaway queries in pg_stat_activity and did the equivalent of "pg_ctl kill".
I don't think this is really pgadmin's fault, but why doesn't PostgreSQL notice that the query requestor has vanished and quit working on the query? Apologies if you think I should ask this on a general PG list.
Thanks,
Dan