Tommy Gildseth <gildseth(at)start(dot)no> writes:
> ERROR: could not read block 6 of relation
> "pg_proc_proname_args_nsp_index": Input/output error
> I'm not really sure what's going on here, and how serious this is.
It's not good --- it means your disk has developed an unreadable block.
You can get out of this particular problem by REINDEXing pg_proc, but
the larger question is whether your disk is on the brink of worse
failures. Might be time to buy a new one.
regards, tom lane