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


Fragmentation does not reduce for some tables


Fragmentation does not reduce for some tables

Author
Message
IT researcher
 IT researcher
SSCommitted
SSCommitted (1.6K reputation)SSCommitted (1.6K reputation)SSCommitted (1.6K reputation)SSCommitted (1.6K reputation)SSCommitted (1.6K reputation)SSCommitted (1.6K reputation)SSCommitted (1.6K reputation)SSCommitted (1.6K reputation)

Group: General Forum Members
Points: 1628 Visits: 1798
I am defragmenting the database as a maintenance work. But i found that some of the databases avg_fragmentation_in_percent does not reduce.But in some article i have seen that fragmentation on small indexes is often not controllable and The pages of small indexes are stored on mixed extents.
So what is the limit for page count for which i can neglect the value of avg_fragmentation_in_percent?

In some databases having page count 100 has shown reduce in fragmentation but some db having page count 68 does not reduce fragmentation. So how can i decide for which condition i should consider checking fragmentation?
GilaMonster
GilaMonster
SSC Guru
SSC Guru (220K reputation)SSC Guru (220K reputation)SSC Guru (220K reputation)SSC Guru (220K reputation)SSC Guru (220K reputation)SSC Guru (220K reputation)SSC Guru (220K reputation)SSC Guru (220K reputation)

Group: General Forum Members
Points: 220891 Visits: 46279
68 pages is too small to worry about. The usual threshold that's mentioned is 1000 pages. Not a hard and fast number, just a guide

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


Perry Whittle
Perry Whittle
SSC Guru
SSC Guru (53K reputation)SSC Guru (53K reputation)SSC Guru (53K reputation)SSC Guru (53K reputation)SSC Guru (53K reputation)SSC Guru (53K reputation)SSC Guru (53K reputation)SSC Guru (53K reputation)

Group: General Forum Members
Points: 53095 Visits: 17672
Aside what Gail has said check the index id for the object. If its a heap then it will naturally contain some fragmentation.

The page allocation marker is 8 pages, any allocations over that will use uniform extents. This is detailed on msdn, sorry but I don't have link at present.

-----------------------------------------------------------------------------------------------------------

"Ya can't make an omelette without breaking just a few eggs" ;-)
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