Q and A: Some questions about output from dbcc memorystatus

Recently I have recieved following question:  A customer of mine is getting this output on an Itanium with 16GB of memory: Memory Manager                      KB —————————— ——————– VM Reserved                           16979888 VM Committed                         217928 AWE Allocated                         14116272 Reserved Memory                     1024 Reserved Memory In Use            0   Q. How can VM Committed be so much less than AWE Allocated, or is this counter…

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Q and A: SQL Server memory allocated outside of Buffer Pool, formerly known as MemToLeave

Q. Under SQL Server 2000 Is the memtoleave concept still valid under 64-bit?  A. Yes. If SQL Server’s component requests memory larger than 8 KB block, the block will be allocated outside of Buffer Pool. Remember, inside of SQL Server, Buffer Pool is preferable memory manager for dynamic allocations. However, it can only serve allocations…

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Q and A: Do I need to run "sp_configure ‘awe enabled’, 1" to make 64 bit version of SQL Server use locked pages?

The answer is No.  The source of possible confusion came from one of my previous posts: http://blogs.msdn.com/slavao/archive/2005/11/15/493019.aspx. I apologize for the confusion. In order to make 64 bit version of SQL Server leverage locked pages all you need to do is to give lock pages in memory privilege to an account under which SQL Server process runs. You…

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Be Aware: 4GB of VAS under WOW, does it really worth it?

By now you have heard a lot about the fact that under WOW a 32 bit process can get 4GB of VAS.   I agree this is great, but I would like you to be aware of something that might hit you really hard.  As it turns out enabling 4GB VAS can be problematic due to…

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Retrieving information about CPUs’ relationships

In order for server side applications to run efficiently on modern hardware they have to understand hardware layout. As we are moving towards multicore and multi node NUMA systems, understanding relationships amongst cores, logical and physical CPU has become very important.  Before we jump into how applications can do it, we need to define what…

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