Hi, It is a DWH query, which has many outer joins. And has "order by" clause as well. The wait is because of sorts only but cant avoid sorting.... ----- Original Message ----- From: Paul Drake To: deepak_blr@xxxxxxxxxxx Cc: ORACLE-L Sent: Wednesday, December 27, 2006 9:32 PM Subject: Re: direct path write wait On 12/27/06, blr_dba <deepak_blr@xxxxxxxxxxx> wrote: Dear Gurus, Am having huge amount of waits on "direct path write event". This event has 98% of the total wait time. Now we want to tune it. Perhaps you might first want to tune the SQL statements that are causing the writes to tempfiles (sorts, hash_joins, GTT usage)? Pd We are using Solaris 9 and Oracle 9.2.0.7 . After examining the system we found that logging is enabled on the mounted UFS file systems. Need your expert advice on the following... > How to know whether the UFS is enabled for asynchronous IO or direct IO? > Which one is better for DWH environments? Pros and cons of each. > Is filesystem cache is involved in both of the above methods? Please suggest the best solution for my environment. Looking forward to your ever valuable feedback. Deepak -- //www.freelists.org/webpage/oracle-l -- -- ALTER SESSION SET EVENTS 'immediate trace name hanganalyze level 4';