Re: SORT_AREA_SIZE question

[Tanel Poder]

Title: Message

Hi!   At the least the wording is incorrect, a user who *connects* to instance, doesn't allocate any sort memory unless there is a need for sort. And if there's need for 100k, only that much will be allocated. And when the sort is over (and rows returned), the sort memory is freed.   On the other hand, if all of the 10 users do huge sorts with sort_area_size 100M, they could have 1GB allocated altogether, even more than that, check my other mail. So yeah, this could introduce paging if having not enough memory. Btw, in mixed environments you could set sort_area_size to small value and create logon trigger which sets s_a_s big for reporting users.. just a thought about swapping issues...    Tanel. ----- Original Message ----- From: Nigel Bishop To: Multiple recipients of list ORACLE-L Sent: Wednesday, June 25, 2003 6:39 PM Subject: RE: SORT_AREA_SIZE question Bart   Each user which connects to the DB will consume that amount of RAM on top of any memory used by the application.  A lot depends on how much memory your server has i.e. 10 users will use at least 1Gb of RAM.  It could induce swapping which is a killer.   Our DSS systems use 20Mb for sort area mind you we have 18Gb temp tablespace   Regards     Nigel Bishop Snr. Oracle DBA ioko Tel DDI:  +44 (0) 1904 435 458 Mobile:   +44 (0) 7881 624 386 Fax:      +44 (0) 1904 435 450 Email:    [EMAIL PROTECTED]           www.ioko.com -----Original Message----- From: Bart Kersteter [mailto:[EMAIL PROTECTED] Sent: 25 June 2003 15:39 To: Multiple recipients of list ORACLE-L Subject: SORT_AREA_SIZE question Hello,   I joined this list last week, so I apologize in advance if I'm asking a question that has previously been answered.   I am responsible for a reporting database/data mart that is approximately 175 GB.  Our main fact table ranges from 1-14 GB depending upon how far along we are into our financial year.  I have large reports that run full table scans on this table daily.  In an effort to keep as much of the sorting in memory as possible I have specified SORT_AREA_SIZE to be 100MB.  Some of the tuning books I am reading now are making me second-guess myself and I am wondering if this is overkill.   Can anyone provide some advice on how large they are setting their SORT_AREA_SIZE values for their DSS systems?    Thanks in advance,   Bart   Please Note The information in this E-mail message is legally privileged and confidential information intended only for the use of the individual(s) named above. If you, the reader of this message, are not the intended recipient, you are hereby notified that you should not further disseminate, distribute, or forward this E-mail message. If you have received this E-mail in error, please notify the sender. Thank you