What is going on PGA /Work Area?

– This script shows how many times work area are executed in
– optimal pass, one pass and mutiple pass.
– Script Name: Work_Area_Execution_Mode
Column optimal_count format 9999999999
Column Optpass_pct format 999
Column Onepass_count format 9999999999
Column Onepass_pct format 999
Column multipass_count format 9999999999
Column Mltpass_pct format 999

Spool Work_Area_Execution_Mode.lst
Select optimal_count, round(optimal_count * 100 / total,2) Optpass_pct, onepass_count , round(onepass_count * 100 / total,2) Onepass_pct,
multipass_count , round(multipass_count * 100 / total,2) Mltpass_pct
from (
select DECODE (SUM(total_executions), 0, 1, SUM(total_executions)) total, SUM(optimal_executions) optimal_count,
SUM(onepass_executions) nepass_count, SUM(multipasses_executions) multipass_count
from v$sql_workarea_histogram
where low_optimal_size <= 8*1024*1024
– As if in my case the pga_aggregate target was 8 Gigs
);

spool Off
– End Script