explain

hello,

there is something I seem missing in explain analyze buffers results when track_io_timing is on:

this is the first lines of an explain: (the request is of no interest, such a result is quite frequent)

Nested Loop Left Join  (cost=941400.77..966327.57 rows=3 width=653) (actual time=52655.694..62533.811 rows=346 loops=1)
  Buffers: shared hit=10068265 read=396705 dirtied=1858 written=218, temp read=429687 written=115187
  I/O Timings: read=79368.246 write=11.486

So, the total execution time is 52655 ms ok

and the total time for i/o is...79368 ms

how ???

thanks