title: SQL Server 2005 Memory Pressure and tempdb writes problem
body: <p>We are having some issues with our production SQL Server.</p>
  
  <p>Server: Dual Quad Core Xeon
  8 GB RAM
  Single RAID 10 Array
  Windows 2003 Server 64-bit
  SQL Server 2005 Standard 64-Bit</p>
  
  <p>There is about 250MB of free RAM on the machine right now.  SQL Server has around 6GB of RAM, and our monitoring software says that only half of the SQL Server allocated RAM is actually being used.</p>
  
  <p>Our main database is approximately 20GB, with about 12GB being used with any frequency.  Our tempdb is at 700MB.  Both are located on the same physical disk array.</p>
  
  <p>Additionally, using Filemon, I was able to see that the tempdb file had 100's or 1000's of writes of length 65536.  Disk queue length was over 100 nearly 80% of the time.</p>
  
  <p>So, here are my questions-</p>
  
  <ol>
  <li><p>What would cause all those writes on the tempdb?  I'm not sure if we have always had that much activity, but it seems excessive and these problems are recent.</p></li>
  <li><p>Should I just add more memory to the server?</p></li>
  <li><p>On high load servers, should tempdb and db files be located on separate arrays?</p></li>
  </ol>