Multiple Instances vs Single / Memory thoughts | SQL Server Performance Forums

SQL Server Performance Forum – Threads Archive

Multiple Instances vs Single / Memory thoughts

<br />[foreword: I’ve just been in this new role for a month now so I am working in with a current infrastructure design and trying to adjust box configs to obtain better performance. All of the servers have C:- & D:- drives that are partitioned off the one visible drive (which is actually a 3x-drive Raid-5 setup). System DBs, Application DBs & backups are on SAN drives attached to the box – tempdb is on D:-drive on the Raid-5.]<br /><br />Only have access to Windows Server 2003 Standard (no Enterprise licences) and MSSQL 2000 Standard (no Enterprise licences) – no use of AWE either (being Std Ed).<br /><br />Q1. Microsoft says that the physical memory limit when using WS2003 standard is 4Gb. So, if I put 8Gb in the box, will it only register the 4Gb and ignore the rest?<br /><br />Q2. *If* I can put 8Gb physically in the box and have it accepted, is there any chance that it could be used against multiple instances of MSSQL2000? Like: 2Gb for O/S; 2Gb for 1st instance; 2Gb for next instance, etc? This question is a long shot seeing that if the O/S won’t use the memory then it won’t recognised for MSSQL to use.<br /><br />-or-<br /><br />Q2. *If* I am only limited to that 4Gb, is there a chance that using the /3GB switch in the boot.ini will allow multiple (2) SQL instances to play nicely together and use all the remaining memory?<br /><br />Q3. I’m trying to convince the network people to give me another drive in the box that is Raid-0 (maybe Raid-1?) so that I can get the Windows swapfile and Tempdb off somewhere on their own so that they can do what they need to do without the Raid-5 performance overhead on files that really don’t need to be backed-up. Is this a good option?<br /><br />Q4. Looking at upgrading a couple of servers (3yr+) running Windows 2000 Server (std) and thinking that if I get a spec’d up machine in and run WS2003 Enterprise, run maybe 16Gb RAM + activate PAE, and run multiple (3? 4?) MSSQL2005 instances in order to consolidate a couple of smaller boxes. Any thoughts?<br /><br />The really hard part is getting Enterprise *anything* as the hand controlling the budget is not saying how much the maintenance costs are so that I can work out which is the better option. All he sees is lowest $’s and then we’re left tearing hair out to obtain performance.<br /><br />Any suggestions greatly appreciated.<br /><br />Feel free to ask for more info if you’ve stopped laughing at me by now…. <img src=’/community/emoticons/emotion-1.gif’ alt=’:)‘ /><br /><br />** A lack of planning on your part does not constitute and emergency on mine. **
Please do not duplicate your post. delete the other one —————————————-
Contributing Editor, Writer & Forums Moderator
http://www.SQL-Server-Performance.Com Visit my Blog at

Uh, yeah…. you had me really confused for a little while there. I didn’t realise that I had duplicated the post (I posted it last night right before going home) Sorry about that. Duplicate post deleted. ** A lack of planning on your part does not constitute and emergency on mine. **