AWE

Question

Post reply

AWE

Viewing 8 posts - 16 through 22 (of 22 total)

You must be logged in to reply to this topic. Login to reply

curious_sqldba SSC-Dedicated Points: 36489 More actions · Answer 1

Here is my config please help..

Microsoft SQL Server 2005 - 9.00.3353.00 (Intel X86)

Microsoft Corporation

Standard Edition

on Windows NT 5.2

(Build 3790: Service Pack 2)

RAM - 25 GB

In this case will i be able to add more than 4 gb ram to sql server?Currently we have 16 gb allocated to sql, does it mean it has no at all? I do not see any errors..please advice..

alen teplitsky SSC-Dedicated Points: 30014 More actions · Answer 2

on x86 if you have more than 4GB of RAM than things like execution plans can be cached above the first 4GB but not the data access. on an old x86 box we used to have we suddenly started to have queries that accessed more than 4GB of data in a single query due to data growth.

i forgot the details but to access this much data on a x86 server i think it pages the data from the paging file to RAM and back again until the query is complete. some processes literally ran 24 hours with no room for error to rerun them since we had other processes scheduled. we upgraded to servers with 32GB of RAM running SQL 2005 x64 and now the same queries can be satisfied in RAM because the process can access some obscene amount of memory. the same processes now run less than 5 hours.

i forgot the math, but it's a mathmatical reason why a 32 bit processor can't access more than 4GB of RAM

myheadhurts Ten Centuries Points: 1262 More actions · Answer 3

i forgot the math, but it's a mathmatical reason why a 32 bit processor can't access more than 4GB of RAM

2³² = 4GB

A processor can only use memory of which it it can reference the binary location. Binary representation of numbers beyond 4294967297 don't fit into 32-bits.

-MarkO

"You do not really understand something until you can explain it to your grandmother" - Albert Einstein

SQLBuddy123 One Orange Chip Points: 28294 More actions · Answer 4

SQLBuddy123

One Orange Chip

Points: 28294

July 29, 2010 at 1:04 pm

#1200009

Hi Sudhakara,

Each application (i.e SQL Server ) as a whole can use 4GB of VAS not individual processes.

Thank You,

Best Regards,

SQLBuddy.

paul.knibbs SSCoach Points: 15320 More actions · Answer 5

molson-927659 (7/29/2010)

i forgot the math, but it's a mathmatical reason why a 32 bit processor can't access more than 4GB of RAM

2³² = 4GB

A processor can only use memory of which it it can reference the binary location. Binary representation of numbers beyond 4294967297 don't fit into 32-bits.

That's what AWE is for, though. All Intel processors (even the 32-bit only ones) have had 36 address lines for a while, which means they can address up to 64Gb of physical RAM; the CPU has to do that internally using an address window which is only 4Gb wide, of course, because that's as much as a 32-bit register can address.