Thank you Marcus for your feedback, You have answered the first question clearly concerning configuration of disks/data volume size.
Do you or any one else know the answer to the second question, namely: *our db instance is about 80% full. What would the drawback be of creating MANY more data volumes, such that the db is only 30% full? Would this overkill have a detrimental effect, and if so, how big? The benefit is of course that the database manager does not have to be so vigilant in terms of not filling the db. I will find this out by experimenting, but it would be like walking in the dark.... It has dawned on me that tweaking a database is no trivial business! Thank you all again, one day I hope to know so much that I can repay ya'll. Regards Jon Loken HLSI >Based on our experience you have to consider the following: - too many volumes will create concurring I/O on the same disk (you'll get a lot of I/O-waits) - each volume needs system ressources (descriptors, threads, memory) - too less volumes will not parallelize We normally create one volume for one disk doing hardware RAID-5, p. ex. if the RAID-5 consists of 10 disks we create 10 volumes. That will make sure that - the I/O is optimally distributed accross the disks - there are enough server tasks to write the data during savepoint So for your installation I'd create an instance with - 3 volumes for data each on separate disk - 1 volume for log area separate from data - 4 - 5 GB each Just my EUR 0.02 Greetz, SIEGENIA-AUBI KG Informationswesen i.A. Markus D�hr -----Original Message----- From: Jon Loken Sent: 06 December 2004 09:49 To: [EMAIL PROTECTED] Subject: optimization of size of data volumes /nr of disks Hi all, We have a database instance that has recently grown to around 9GB in size. I have some questions wrt performance regarding hardware and db software. -At the moment I have about 45 data volumes on 1 disk (all together have 3-4 disks available), each data volume being around 200MB. This configuration will be adjusted and tweaked according to your feedback. In my mind one must find a balance between having as small data volumes as possible (easier on maxdb/memory?) and having as few data volumes as possible (fewer file references?). *what is the drawback/benefit of having large data volumes, each being for instance 1 GB as opposed to small data volumes? Would for instance using all 3 disks, and placing 3 data volumes on each disk, each volume being 1GB big be a good solution? *our db instance is about 80% full. What would the drawback be of creating MANY more data volumes, such that the db is only 30% full? Would this overkill have a detrimental effect, and if so, how big? The benefit is of course that the database manager does not have to be so vigilant in terms of not filling the db. Many thanks for your help! Regards Jon Loken -- MaxDB Discussion Mailing List For list archives: http://lists.mysql.com/maxdb To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] -- MaxDB Discussion Mailing List For list archives: http://lists.mysql.com/maxdb To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
