Mail server is too slow to deliver the mail to internal domain

Question

Hi,
My mail server faster enough to send the mails to other domains, but when i try to send mail to my own domain it too slow some time it take 30 t0 40 minutes to deliver the mail.
Please help
Thanks,
Gulab Pasha

Answer 1

You should use statspack to check what are the main waits.
Some indicators to check :
- too many fts/excessive IO => check sql statements (missing index, wrong where clause)
- explain plan for most important queries : using cbo or rbo ? If cbo, statistics should be up to date. If rbo, check acces path.
-excessive logfile switch (> 5 per hour) : increase logfile or disable logging
- undo waits => not enough rollback segments (if you don't set AUM)
- data waits => alter initrans, pctfree, pctused
- too many chaining rows => rebuild set of datas or rebuild table
- too many levels in indexes => rebuild index
- excessive parsing : use bind variable or alter parameter cursor_sharing
- too many sort on disks => increase sort_area_size and create others temporary tablespace on separate disks
- too many blocks reads for a row => db_block_size too few or too many chaining rows
- too many lru contention => increase latches
- OS swapping/paging ?
Too improve performance :
- alter and tune some parameters : optimizer_mode, sort_area_size, shared_pool_size, optimizer_index_cost_adj, db_file_multiblock_read_count...
- keep most useful packages in memory
- gather regularly statistics (if using cbo)
How do your users access to the db ?
Jean-François Léguillier
Consultant DBA