SQL Server Admin 2014 :: Rule Of Thumb For Sizing Log Space During Index Maintenance?
Sep 13, 2014
I've been fixing some issues lately where weekly maintenance has been causing logs to grow and filling disks.
Is there any rule of thumb for allocating log space for doing reorgs and rebuilds in a worst case scenario? I'm thinking 3x the largest database size?
I've been watching them run on databases in the range of 50GB where the logs are growing well over that for rebuilds or even reorgs. Once you have a few databases like this on a server, you can suddenly eat through a lot of disk space just for holding logs during maintenance.
I'm trying to determine how much space I would need for my data drive and log file drive to do index rebuild. I have a database which is 100gb, it is in simple recovery mode. let me know what to have a look at to determine how much space.
It's often said or done that when inserting or updating into a 'large' table that disabling the non-clustered indexes can is needed for performance.
Now I know the obvious way to find out if this is best or not is by testing the different options. I was wondering if there was a rule of thumb to this?
Say you have a table with half a billion rows and 4 non-clustered indexes and are only updating half a million rows then sometimes disabling every night and re-enabling can take way more time than the actual update. Haven't found an articles advising to disable them when a table is over X rows and you are updating Y% of them...
This is a general question about data modeling. I'm more curious than anything else.
There is much talk about over-training data model, and I'm sure there are under training as well. As a rule of thumb, depending on the algorithm, what is a good ratio of attributes vs data points?
We have deleted 120GB of data but space did not released even after 2 days. Is there any reason for this? tell me how exactly it releases the space after truncating a 120GB table?
While i execute dbcc sqlperf(logspace); I get following values.
Database NameLog Size (MB)Log Space Used (%) master 16.17969 13.30275 tempdb 7.429688 61.7245 model 0.7421875 45.78947 msdb 5.554688 25.87904 distribution 2808.93 0.8172179 BANKDB 23438.87 48.20037 WSMIRSDB 109.7422 4.839111
For database BANKDB , Log Space used(%) is 48.83% and Log size is about 23438.87 where as my database size of BANKDB is 60 GB. FULL database and Log back is done every day night one time. My database is performing slow now.
Do we need to take log backup frequently like once a 1 hour so that Log space used will be less. Same query is taking more time to execute than before in same database is it because of log file has increased.
I do index organize and rebuild once a week and stats apply nightly.
Is it correct once log space size is increasing more than 10%. Do we need to take log backup?
I was trying to configure maintenance plan to take nightly full database backup and Log backup. I was trying to configure it like in attached file. Any links that i can follow and configure as in attached file.
How do i find Total allocated space and used space of a memory optimized filegroup?
use memory_optimized_db Go select (SUM(size)*8.0)/1024.0 as Space, FILEGROUP_NAME ( data_space_id ) , type_desc from sys.database_files group by data_space_id,type_desc;
above query gives "current used size of the container " of memory optimized file group but doesn't give Total space detail.
In SQL 2008 R2, if we clone an environment including SQL server, the maintenance plans retain a connection string to the source/original server they got cloned from and are not editable. But, I was able to use a work around by editing them in BIDS and saving them back on the server. But now with 2014, I am facing two issues:
1.I still can edit the package to correct the server connection, with SSDT; but the option to save back to the server is not available any longer!
2.I used to be able to see all my plans under SSIS in 2008 R2 but not in 2014 now. Although, they are listed in SSMS!
I am looking for a table where Maintenance Clean Up Task configuration is stored. For example, Delete file older than the following - which is 2 days. Which table can I retrieve the setting in msdb ?
Dead lock is coming in select query in application because of index. It is identified after enabling trace in database and identified by reading deadlock xml file. After index removal, deadlock is not coming in same query. But it is affecting query's performance slightly. Is it correct way to remove index if dead lock is coming because of index?
We have a database with a table that contains around 180m records. Each day a further 70k are inserted. No records are ever deleted as this table is used for archiving only.Users are required to perform SELECTs on this table constantly but due to the high number of INSERTs the indexes become very fragmented very quickly. My aim is to avoid daily rebuilds of the indexes which is what our software house is telling us we have to do.
This is the DDL for the table:
CREATE TABLE [dbo].[Inventory]( [EAN] [bigint] NOT NULL, [Day] [smalldatetime] NOT NULL, [State] [int] NOT NULL, [Quantity] [int] NULL, [StockValue] [float] NULL, CONSTRAINT [PK_Inventory] PRIMARY KEY CLUSTERED
[code]...
There are also three clustered Indexes on this table each referencing a single column. The problem from my side is that I cannot understand why the three columns in a primary key would also be configured as non-clustered indexes.My solution would be one of the following:
1. Accept the tables are going to be fragmented and require a daily rebuild (don't like this one!)
2. Partition the table
3. Remove the non-clustered Indexes and let the clustered index for the primary key do the work.
I would like to put a Clustered Index on a date column in a current heap, but one question/concern.This heap every month has thousands of rows deleted and even more added later. How much of an issue will this cause the Clustered Index as far as page splits? I was thinking Fill Factor of 70%.I would normally just test and still will on Dev box, but my Dev box is much smaller than production as far as power.
We use SQL server always on feather on my database and we distribute statement on main database server and mirror database server for raise performance.
My police for split statement is DML (insert, update and delete) statement go to main DB and Read Data (select) statement go to mirror DB.
I want know can I use different index on main DB and mirror Database?
Because some index are used in mirror DB not used in main database.
We face slow performance issue for like taking long time for same query execution after We apply index rebuild and reorganize index. But, after execution of query or procedure for 2 -3 times, performance will be faster. I have following questions
1 do we need to update stats after we rebuild an reorganize index. 2. is it will be slow for 1-2 times for every query and stored procedure execution after we rebuild and reorganize index?
I want to set up a database role so that users can use sp_readerrorlog through SSMS. It does a check on membership in the securityadmin role.
I have tested it and can see you can grant execute on xp_readerrorlog but the SSMS GUI uses sp_readerrorlog.
I thought I could create a user/certificate and add the signature to sp_readerrorlog but it's not permitted (likely because it's not a normal database object).
So the other solution is to add the users to the securityadmin role but then explicitly deny alter any login (best done with a custom server role in 2012+ but otherwise just manually in 2008). I tested this out and it works, I'm not able to alter any logins or increase my own permissions, I also did a check of what's reported from fn_my_permissions(null, null) and it shows minimal permissions like I'd expect.
1. I created a maintenance plan using Visual Studio 2013 (nothing fancy pretty basic) 2. Using ssms 2014 I imported it (the dtsx file) under the Integration Services and it appeared there successfully 3. I connected to the Database Engine again using ssms 2014 - my expectation was to see it under the Management > Maintenance Plans folder but it was not present.
If I install an instance with Windows Only authentication, and then change it to Mixed Mode, if I enable the sa login, the password has already been set. What is the default? If it's generated, how secure is it? Is the password generated? What algorithm is used for that?
My sql databases in SQL Server 2014 has the status "suspend" as I saw in SQL Management Studio. I can't restore to serviceable condition sql databases through standard procedures. I need to restore .mdf file.
I am using a monitoring system where I can monitor a numeric SQL result assuming the result is one field and one row.I would like to do this to say monitor the free available space or percentage on say the Master database. DBCC SQLPERF gives me a few columns and results for all databases on the server.
In our environment applications are using a DNS name which points to the physical server ip address. Now we are planning to move to 2014. We are planning to have servers in different subnets so we will be having two ip adresses for listener. How we can point the DNS to the listener ips? If failover happens can the DNS point to the exact ip address of the listener where it's primary node?
"Process 0:0:0 (0x1e10) Worker 0x00000006B6D341A0 appears to be non-yielding on Scheduler 13. Thread creation time: 12906028806348. Approx Thread CPU Used: kernel 0 ms, user 0 ms. Process Utilization 13%. System Idle 84%. Interval: 70189 ms."
Is it better to run the profiler or performan counter?
What are the filters we have to select in the profiler to monitor the Sql server
I have a SQL server box running 2014 reporting services. I have another server running IIS v8.
I would like to be able to connect to the IIS site and be given the SSRS report browser.
So externally if I browse to [URL], I am presented with the report server interface, the same as if I browse to http://xxx.xxx.xxx.xxx/reports internally.
What is the best approach for a read only copy of a database that is ~ 1TB. The primary database is fed nightly with an ETL process. We are currently trying to duplicate the ETL to read only server but that process is not going well. So we are looking at other options to let SQL make the copy.
The primary database is on a Win12R2 with SQL 12 or 14, a 2 node A/P failover cluster.
The read only copy will be on a Win12R2 with SQL 12 or 14. It is not a requirement to fail over to the read only copy if the primary should go down.
What would best the approach to accomplish the end result?
