Re: Question regarding rollback segment

parris_at_walleye.esp.bellcore.com (Parris Geiser) wrote:

>William,
> The fact that your MAXEXTENTS is 505 indicates to me that there
> is a misunderstanding on your part regarding extents. So, to be
> sure your database is created properly (along with your tables)
> it would be helpful to supply the exact parameters that you are
> using.
> parris geiser

Why does that indicate a misunderstanding on his part? If they are using an 8k block size, I believe they will get 510 or so extents on that particular system. Maxextents varies by platform (i know that 510 max with 8k block size on a Pyramid for example works just fine).

Using a 16k block size would result in even more. The number of extents allowed in a table is a function of the block size the database was created with.

>William D. Hankard (wdh_at_epsilon.com) wrote:
>> Hello,
 

>> We are running Oracle 7.1.6 on an HP 9000 T500 running
>> HP-UX 9.04
 

>> Here is the problem we are having; our rollback table
>> space is 3.0Gbytes in size.
 

>> Our initial extent is 5Mbytes
>> Our next extent is 5Mbytes also.
>> Our OPTIMAL parameter is set to 220Mbytes.
>> Our MINEXTENTS is 2
>> Our MAXEXTENTS is 505
>> Our Pro*C program commits after every 100 updates
>> A row size is less than 200Bytes
 

>> After about 100000 updates which is a 1000 commits, I get the 1555
>> Oracle error:
 

>> 01555, 00000, "snapshot too old (rollback segment too small)"
 

>>
>> We have tried the following to fix the problem:
>> a. commit after every row
>> b. commit after every 50 rows
>> c. rollback segment in a non-RAID device
>> d. 20Mbyte extents.
>> e. restarted Oracle (reboot etc)
>> f. recreated rollback tablespace
 

>> None of these things have helped. Any suggestions or insight into this would
>> be of great help. Thanks in advance.
 

>> --
>> ==========================================================================
>> William D. Hankard Epsilon Data Management
>> 50 Cambridge Street Burlington MA. 01803-4692
>> Voice:(617)273-0250 Ext. 6738 High Performance Computing
>> Fax:(617)272-1760 wdh_at_epsilon.com
>> ==========================================================================

Thomas Kyte
tkyte_at_us.oracle.com
Oracle Government Received on Sat Jul 15 1995 - 00:00:00 CEST