In AWR report, what is "Batched IO (bound) vector count" ?

Hi All,

I am looking at AWR report, in section, Instance Activity Stats.

First stat is "Batched IO (bound) vector count". What does that stand for? I tried searching in documentation.

Actually, in Instance Activity Stats, first few lines are, Batched IO (bound) vector count, Batched IO (full) vector count, Batched IO (space) vector count, Batched IO block miss count, Batched IO double miss count. Where can I find the details/meaning for these statistics ?

Thanks in advance