Обсуждение: Stripping raid vs. table spaces
Short question: Is it enugh to have stripping on a disk array? Are table spaces then of less use than the actual stripping? So will just stripping give me more O/I-performance?
On 6/9/05, KÖPFERL Robert <robert.koepferl@sonorys.at> wrote: > Short question: > > Is it enugh to have stripping on a disk array? > Are table spaces then of less use than the actual stripping? So will just > stripping give me more O/I-performance? Short answer: if you make one striping partition -- you have better overall performance. if you distribute tables using tablespaces -- you make tables performance more independant from other tables. I.e. large load on one table has less impact on the load on the other table. Personally I would keep indexes on one set of drives and data on other. All depends on your setup.
On Thu, 2005-06-09 at 02:16, KÖPFERL Robert wrote: > Short question: > > Is it enugh to have stripping on a disk array? > Are table spaces then of less use than the actual stripping? So will just > stripping give me more O/I-performance? The answer is, it depends. If you had some large number of drives to put in a RAID array, along with a fast RAID controller and lots of battery backed cache set to write-back, then it is unlikely you would get any better performance from putting tables and indexes on lots of different discrete drives. Of course, you can use both, putting table spaces on top of different stripe sets. The important thing to consider is your usage pattern. Will you be writing in several small streams and reading in one or two big ones? Or vice versa? Or will you have many read/write transactions in transit at once? Will you have a few heavy traffic tables and lot of low traffic ones? On and on. There's a big difference between a data warehouse / OLAP and a transactional engine / OLTP setup. Note that there is probably better info on this in the -performance archives than in the -admin ones... ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
On Thu, 2005-06-09 at 02:16, KÖPFERL Robert wrote: > Short question: > > Is it enugh to have stripping on a disk array? > Are table spaces then of less use than the actual stripping? So will just > stripping give me more O/I-performance? The answer is, it depends. If you had some large number of drives to put in a RAID array, along with a fast RAID controller and lots of battery backed cache set to write-back, then it is unlikely you would get any better performance from putting tables and indexes on lots of different discrete drives. Of course, you can use both, putting table spaces on top of different stripe sets. The important thing to consider is your usage pattern. Will you be writing in several small streams and reading in one or two big ones? Or vice versa? Or will you have many read/write transactions in transit at once? Will you have a few heavy traffic tables and lot of low traffic ones? On and on. There's a big difference between a data warehouse / OLAP and a transactional engine / OLTP setup. Note that there is probably better info on this in the -performance archives than in the -admin ones... ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend