SQL Clone
SQLServerCentral is supported by Redgate
 
Log in  ::  Register  ::  Not logged in
 
 
 


Max server memory


Max server memory

Author
Message
Robin
Robin
Ten Centuries
Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)Ten Centuries (1.2K reputation)

Group: General Forum Members
Points: 1184 Visits: 331
I have a SQL2008R2 server that pretty consistently hogs about 47GB of the 48GB of RAM on the box. One of the sys admins has asked me to change the limit. He didn't specify what to set it at. It's currently just the default (dynamic). I've never played with this and I'm iffy about it. It's a critical server. It's our SharePoint database, which houses several business-critical functions and it's hit this hard 24x7x365. My fear is that if it's consistently using all of the RAM, it may be because it needs it. If I crank that limit down, is my server going to crash?
SQLRNNR
SQLRNNR
SSC Guru
SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)

Group: General Forum Members
Points: 143351 Visits: 18649
It is a best practice to set a max server memory limit. Right now, you are starving the OS of memory and in the end you could be causing contention for memory.

You should reduce max memory for sql server. Here is an article with a guideline and formula.

http://www.sqlskills.com/blogs/jonathan/how-much-memory-does-my-sql-server-actually-need/

Jason...AKA CirqueDeSQLeil
_______________________________________________
I have given a name to my pain...MCM SQL Server, MVP
SQL RNNR
Posting Performance Based Questions - Gail Shaw
Learn Extended Events

Gary Gwyn
Gary Gwyn
SSC Veteran
SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)

Group: General Forum Members
Points: 223 Visits: 658
If no maximum is set, then SQL uses as much RAM as it needs. You can set a maximum, say 44,032 MB -- allows 4GB for OS operations. One catch - you must restart the SQL service before the changes take effect. You will have to schedule a momentary outage.

Blog: http://sqlexchange.wordpress.com
SQLRNNR
SQLRNNR
SSC Guru
SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)

Group: General Forum Members
Points: 143351 Visits: 18649
Gary Gwyn (2/19/2014)
If no maximum is set, then SQL uses as much RAM as it needs. You can set a maximum, say 44,032 MB -- allows 4GB for OS operations. One catch - you must restart the SQL service before the changes take effect. You will have to schedule a momentary outage.



No. The change is immediate and no need to restart SQL Server.

Jason...AKA CirqueDeSQLeil
_______________________________________________
I have given a name to my pain...MCM SQL Server, MVP
SQL RNNR
Posting Performance Based Questions - Gail Shaw
Learn Extended Events

GilaMonster
GilaMonster
SSC Guru
SSC Guru (545K reputation)SSC Guru (545K reputation)SSC Guru (545K reputation)SSC Guru (545K reputation)SSC Guru (545K reputation)SSC Guru (545K reputation)SSC Guru (545K reputation)SSC Guru (545K reputation)

Group: General Forum Members
Points: 545674 Visits: 47728
See Chapter 4 of http://www.red-gate.com/community/books/accidental-dba for a lot of discussion of memory and some guidelines around the setting of this value.

The setting takes effect immediately, no restart is required.

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


Gary Gwyn
Gary Gwyn
SSC Veteran
SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)SSC Veteran (223 reputation)

Group: General Forum Members
Points: 223 Visits: 658
Boy, do I feel stupid. I stand corrected. I just tested this via the GUI and a script and the change is effective immediately.

I'm not sure where I picked up my misinformation. Thanks for the correction, as it will make my life easier.

Blog: http://sqlexchange.wordpress.com
SQLRNNR
SQLRNNR
SSC Guru
SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)SSC Guru (143K reputation)

Group: General Forum Members
Points: 143351 Visits: 18649
Woohoo - that's a win then. Cool

Jason...AKA CirqueDeSQLeil
_______________________________________________
I have given a name to my pain...MCM SQL Server, MVP
SQL RNNR
Posting Performance Based Questions - Gail Shaw
Learn Extended Events

Go


Permissions

You can't post new topics.
You can't post topic replies.
You can't post new polls.
You can't post replies to polls.
You can't edit your own topics.
You can't delete your own topics.
You can't edit other topics.
You can't delete other topics.
You can't edit your own posts.
You can't edit other posts.
You can't delete your own posts.
You can't delete other posts.
You can't post events.
You can't edit your own events.
You can't edit other events.
You can't delete your own events.
You can't delete other events.
You can't send private messages.
You can't send emails.
You can read topics.
You can't vote in polls.
You can't upload attachments.
You can download attachments.
You can't post HTML code.
You can't edit HTML code.
You can't post IFCode.
You can't post JavaScript.
You can post emoticons.
You can't post or upload images.

Select a forum







































































































































































SQLServerCentral


Search