Dan 11 ms isnt a terrible average at all. Do you have a version where you get the distribution of times though? you could be hiding fast and slow disks in the average. The frequency distribution will show this. On 24/09/2008, Daniel Fink <daniel.fink@xxxxxxxxxxxxxx> wrote: > In a recent optimization effort, I found what I think are high physical > read times. For example, a single block read was averaging 11 > milliseconds with a max of over 1 second (tkprof output). For this > session, single block reads consumed over 80% of the response time, so > this is of concern. > > We are running Oracle 10gr1 on AIX with an IBM storage array (shared > amongst many servers). I suspect there is some optimization that can be > done at the storage array level. If 11 milliseconds is well above > average, this will help in engaging that team in the process. > > For those of you running statspack. AWR or other monitoring tools, what > are the average single block read times you are encountering on a good > system? If you are running on an IBM storage array, have you found any > specific issues/fixes? > > Regards, > Daniel Fink > > -- > Daniel Fink > > OptimalDBA.com - Oracle Performance, Diagnosis, Data Recovery and Training > > OptimalDBA http://www.optimaldba.com > Oracle Blog http://optimaldba.blogspot.com > > Lost Data? http://www.ora600.be/ > > -- > //www.freelists.org/webpage/oracle-l > > > -- Niall Litchfield Oracle DBA http://www.orawin.info -- //www.freelists.org/webpage/oracle-l