How best to expand IQ by 4Tb

[Former Member]

What is the best option to allocate 4Tb? ------------------------------- Number is CPU is 16 and not likely to change. Current Sybase IQ Configuration MAIN IS 7TB Sybase IQ User Main dbsapce has 16 * 440gb dbfiles -> 16 Main luns. Sybase IQ Temp dbsapce has 16 * 51Gb dbfiles -> 16 temp luns. Sybase IQ System dbsapce 100Gb dbfiles How best can one configure on IQ with extra space allocation. Option 1: Initially add 4 *440gb extra dbfiles (add 2Tb) and subsequently increase Sybase IQ User Main dbsapce has 20 * 440gb dbfiles Sybase IQ  Temp dbsapce has 20 * 51Gb dbfiles Sybase IQ System dbsapce 100Gb dbfiles Option 2: Add all 9 *440gb extra dbfiles ( all 4Tb) Sybase IQ User Main dbsapce has 25 * 440gb dbfiles ->Sybase IQ  Temp dbsapce has 25 * 51Gb dbfiles Sybase IQ System dbsapce 100Gb dbfiles The below options is likely to be more work but if the performance is not compromised, they might be considered. Option 3: Rebuild all 11Tb over the 16 dbfiles Sybase IQ User Main dbsapce has 16 * 650gb dbfiles Sybase IQ  Temp dbsapce has 16 * 51Gb dbfiles Sybase IQ  System dbsapce 100Gb dbfiles

[markmumy]

If you want to simply increase the size of your database, choose a device size that makes sense for your environment and use that.  I prefer to have all IQ devices be the same size so that you don't end up with lots of smaller, full devices thus creating hot spots on the fewer, larger devices.

If you want o redistribute your data across all devices after you've added the 4TB, that can be done, too.  You can simply run sp_iqrebuildindex on certain tables/columns.  This will spread the data across all available devices.

If you know that you will need 4TB, then I would add all 4TB.  The issue with option 1 is that if you had fewer devices, they will get full faster.  When you add the remaining devices, you will then have full devices and empty devices leading you to redistribute your data yet again.  If you add all 4TB today, you will evenly distribute the data over all available storage today and leave yourself room for growth.

Mark

[Former Member]

4TB is not a whole lot.  I say just create the devices in either option during your normal maintenance window.

jason