How much memory left for the Os only?

Question

How much memory left for the Os only?

sql-lover

SSCoach

Points: 18530
More actions
November 12, 2012 at 9:39 am

#265290

Hi,
Got a pretty old MS-SQL 2005 server that I've been trying to optimize for several months. So far, so good. Most of the changes were done at code level (dropping and adding proper Indexes or writing better T-SQL code) But I am to a point that further code optimization is not possible.
Here a few Perf. Counters (data collection run for a full week)
Memory
Available MBytes: 1500.120
Page Faults/sec 2060.30
Pages/sec 12.99
Physical Disk
Avg disk sec/read 0.017
Avg disk write/read 0.011
Processor
%Processor time 6.635
Buffer Manager
Page life expectancy 4360.348
Target Server Memory 12600.834
Total Server Memory 12600.834
MS-SQL server top max memory is 12.5GB. Os RAM is 16GB. I was planning to increase MS-SQL RAM 500 or 1000 MB more. Based on the data above, would that be pushing the server too much?
I honestly have never had to push MS-SQL this way before, but it is one of the 1st servers I have to administer that really runs with very old hardware and can't upgrade or change any time soon.
Any comments about my suggestion of increasing MS-SQL RAM value? Engine is MS-SQL 2005.
Thanks in advance,

Viewing 5 posts - 1 through 5 (of 5 total)

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

Gail Shaw SSC Guru Points: 1004514 More actions · Answer 1

Chapter 3: http://www.simple-talk.com/books/sql-books/troubleshooting-sql-server-a-guide-for-the-accidental-dba/

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

sql-lover SSCoach Points: 18530 More actions · Answer 2

GilaMonster (11/12/2012)
Chapter 3: http://www.simple-talk.com/books/sql-books/troubleshooting-sql-server-a-guide-for-the-accidental-dba/

Thanks for reply.

Do you mind be more specific?

I actually have the paper book version at home. Re-download the free PDF version after your post. Chapter 3 is about CPU pressure. My question is more towards the available RAM I have vs increasing existing value for MS-SQL max RAM setting. I do believe that for dedicated SQL servers, 500 MB left for Os should be ok.

Upgrading CPU or hardware is just out of question on my problems.

Again, thanks for reply.

Gail Shaw SSC Guru Points: 1004514 More actions · Answer 3

sql-lover (11/12/2012)
GilaMonster (11/12/2012)
Chapter 3: http://www.simple-talk.com/books/sql-books/troubleshooting-sql-server-a-guide-for-the-accidental-dba/
Thanks for reply.
Do you mind be more specific?

Sorry, chapter 4.

Jonathan details his algorithm for calculating the max server memory for any value of total installed memory towards the end of the chapter.

If you want the page no, I'll dig out my copy from whereever it is.

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

sql-lover SSCoach Points: 18530 More actions · Answer 4

GilaMonster (11/12/2012)
sql-lover (11/12/2012)
GilaMonster (11/12/2012)
Chapter 3: http://www.simple-talk.com/books/sql-books/troubleshooting-sql-server-a-guide-for-the-accidental-dba/
Thanks for reply.
Do you mind be more specific?
Sorry, chapter 4.
Jonathan details his algorithm for calculating the max server memory for any value of total installed memory towards the end of the chapter.
If you want the page no, I'll dig out my copy from whereever it is.

Thanks, I will take a look.

I haven't checked yet, but it may be a similar one to the equation or formula given by Brent Ozar on his SQL 2008 Internals and Troubleshooting book, when sizing memory.