Hello,
I understand that SQL2005x64 bits ignore AWE enable in SQL because it can address all the memory without having to use AWE. How about 32 bits SQL2005, does it support AWE enabled?
I emailed the guy who presented on the topic at PASS a few weeks ago and here's his response. It may be a bit overkill, but hopefully answers your question. :)
This is a bit complicated.
Yes, SQL 2005 supports AWE and the behavior is different from 2000 in it is dynacmically adjustable with no server restart.
On x64 and I64 regardless of the AWE setting we use the underlying windows AWE mechanism to allocate the memory. This is a performance optimization because using this AWE mechanism in the kernel requires one less lock. However there is no mapping/unmapping from lower to upper memory as you would in the 32-bit world – just flat addressing. Customers can get confused when they look at DBCC MEMORYSTATUS on 64-bit and see AWE pages allocated.
Also, on 64-bit make sure that the SQL service account needs to be granted “lock pages in memory”.
Also, take a look at Slava’s BLOG – it explains many of the memory behaviors of the engine in great depth.
?http://blogs.msdn.com/slavao
Thanks,
Sam Lester (MSFT)
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