Gary On modern disk subsystems there is not a lot to be gained - there *is* a trick however if you are doing very large unindexed SELECTs on very VERY large files...........i.e.
Make the file separation large - and an exact multiple of the physical disk subsystem transfer unit size - SELECTs fly The penalty of course is for updates to the file - as these can take longer. But hey - the only reason you would do this is if you have a "pain" in batch processing (such as overnight operational windows). Of course having a lot of buffer cache also helps a lot. Especially with the overheads of RAID 5. Regards JayJay -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: 31 October 2005 19:42 To: [email protected] Subject: [U2] [UV] AIX Backup, Format Disk, Restore Does anyone out there still do this (if you ever have)? Take a backup of the file systems (in our case, AIX UNIX), format the disks clean, then restore the data back down to lay it back contiguous. Are there any (noticeable) I/O advantages to doing this for a UniVerse database on today's servers? Provided our files are properly sized, of course. Our Systems guys are itching to do this. Thanks, Gary P. Canedy Database Analyst ProMutual Group (617) 757-6775 ----------------------------------------------------------- This email and any files transmitted with it are intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. If you received this email in error, please contact the sender immediately and delete this email from your system. If you are not the named addressee, you should not disseminate, distribute, print, or copy the email, or take any action in reliance on its contents. ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/ ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/
