Question- Why am I getting 428 pages for which there is no corresponding DB object? Why are so many pages present in sys.dm_os_buffer_descriptors but are missing from sys.allocation_units.
We are troubleshooting a performance problem and the test result is slow the 1st time but the subsequent runs are faster.. Logging out of application and log back in ( connecting to a new database session) did not clear the buffer cache as I thought it would.. When does the database clear the buffer cache? Is it not per database session?
I can issue CHECKPOINT and then run DBCC DROPCLEANBUFFERS to clear the buffers in the disk. But since we are testing from the application,do we need to run these commands via application code to clear buffer/per database session OR can we run these commands from a management studio session?
I have a virtual server (VMware ESX) with 64GB RAM running a single instance of SQL 2012 SP1. The max memory config is set to 59392 (58GB).
The Page Life Expectancy for this server has been averaging well under 10 mins for the last few days, according to our monitoring.
I have been checking the amount of data in the buffer cache periodically during the day with the below query, which seems to show that there is never more than about 10GB of data at any one time, frequently dropping below 5GB:
SELECT COUNT(*) AS BufferPages, CONVERT(decimal(10, 2), COUNT(*) / 128.0) AS BufferMB FROM sys.dm_os_buffer_descriptorsWhy would the amount of cached data be so low (and cause so much churn)?
I am aware that other things will require some of that memory (plan cache etc.) but with Max Mem of 58GB, I would expect there to be a much higher amount of actual cached data at any one time. I did the same checks on another VM with the same amount of RAM/Max Mem setting, and there was 50GB of data in the cache, with PLE measured in hours.
I'm getting an alert which states that both my Buffer Cache Hit Ratio and PLE are low on one of my SQL Servers though I'm not sure how to correctly check this.
I ran:
SELECT object_name, counter_name, cntr_value FROM sys.dm_os_performance_counters WHERE [object_name] LIKE '%Buffer Manager%' AND [counter_name] = 'Buffer cache hit ratio'
Which gives me the Buffer Cache Hit Ratio, cntr_Value of 9 though its constantly dipping between 3-3000 and is never steady and I'm unsure if this is normal.
I also ran:
SELECT object_name, counter_name, cntr_value FROM sys.dm_os_performance_counters WHERE [object_name] LIKE '%Buffer Manager%' AND [counter_name] = 'Page life expectancy'
Which gives me the Page life expectancy of 209061.
If these values would cause concern and if this is a normal Buffer Cache Hit Ratio? It's constantly dropping from high or low from what I can see. These scripts were pulled from another forum and I'm assuming they're showing the correct values.
Is there a way to drop clean buffers at the database level instead of the server/instance level like the undocumented €œDBCC FLUSHPROCINDB (@dbid)€?? Is there a workaround for €œdbo€? to be able to flush procedure and data cache without being elevated to €œsysadmin€? server role?
PS: I am aware of the sp_recompile option that can be used to invalidate cached execution plans. Thx.
I am trying to find out CPU utilization from the history using process.%processor time. I am having dual core CPU with 2 numa nodes each having 16 logical cpus bind to it.
how to calculate the CPU utilization using perfmon.I tried to use SQL query which gives CPU history using SQL DMV, but I am unable to get the exact value. Because in between I have used the same querry to capture my CPU usage on the run day, the value on run day and the query which iam tryting to pull out is different. I am using the same query to pull the history data with providing the date.
-- Get CPU Utilization History (SQL Server 2008 and above)
DECLARE @ts BIGINT SELECT @ts =(SELECT cpu_ticks/(cpu_ticks/ms_ticks) FROM sys.dm_os_sys_info); SELECT SQLProcessUtilization AS [SQLServer_Process_CPU_Utilization], SystemIdle AS [System_Idle_Process], 100 - SystemIdle - SQLProcessUtilization AS [Other_Process_CPU_Utilization],
Help, have recently upgraded from 6.5 to 7.0 and have come across a problem with performance. The problem appears to relate to the buffer cache being flushed, the buffer cache hit ratio drops from 98% to 0% in a matter of a second. It then very slowly grows, then is flushed again, then increase slowly upto 30%.
Does any one have any ideas as to what would flush the buffer cache?
How to alter all objects in database i want to find if can any syntax errors in my database after restoring from sql 2008 to 2012. I Can create as test and drop them but trying to find a way to alter proc , views and functions..
My problem is that I cannot completely clean buffer cache on SQL Server 2005 version 9.00.2047.00 (probably SP1).
Right after I run DBCC DROPCLEANBUFFERS in the context of my database (this is development server, and so far I am only the one who is working with a particular database), I run a script that quetries sys.dm_os_buffer_descriptors view also from the context of my database to make sure that the buffer cache is really clean. However it shows large number of entries totalling 42 MB.
I ran both DBCC an the script in the past too, and it always showed nothing in the results, that means that buffers were really clean. The reason why I am running this is for benchmarking of existing and new application.
Does anybody have any idea, suggestions, how to troubleshoot this issue ? I already closed all connections to this database, but rebooting the server is not an option since other people are also working on it.
This issue just happen recently. The buffer cache ratio went from > 90%to 50% and has slowly been climbing back up over 8 hours or so. Itscurrently @ 76%. Is this something I should take action on immediately?It seems to be coming back to normal...
HiI have trouble with MSSQL2000 SP4 (without any hotfixes). During last twoweeks it start works anormally. After last optimalization (about few monthsago) it works good (fast, without blocks). Its buffer cache hit ratio wasabout 99.7-99.8. Last day it starts work slow, there was many blocks anddedlocks. There are no any queries, jobs and applications was added. Nowbuffer cache hit ratio oscilate about 95-98. I try update statistics andreindex some hard used tables, but there is no effect or effect is weryshort (after few hours problem return).Mayby somene know what it could be?Is it possible to estimate how each table (using DBCC SHOW_STATISTICS orDBCC SHOWCONTIG or others) how the table affect on total buffer cache hitratio?Marek---www.programowanieobiektowe.pl
I can use Profiler to see database usage activity. However, in addition to it, is there a good query I can use to see whether user databases are being used (last select, last update, last alter or last delete etc., with date/time stamp)?I am looking for both SQL2000 and SQL2005 as we need to decommission some of the older servers.
-- This stored procedure will let you search through your database -- to find various objects that contain a particular string. -- For example, you may want to see all tables and views that contain -- a particular column.
use master IF (object_id('sp_FindReferences') IS NOT NULL) BEGIN PRINT 'Dropping: sp_FindReferences' DROP procedure sp_FindReferences END PRINT 'Creating: sp_FindReferences' GO CREATE PROCEDURE sp_FindReferences ( @string varchar(1000) = '', @ShowReferences char(1) = 'N' ) AS /****************************************************************************/ /* */ /* TITLE: sp_FindReferences */ /* */ /* DATE: 18 February, 2004 */ /* */ /* AUTHOR: WILLIAM MCEVOY */ /* */ /****************************************************************************/ /* */ /* DESCRIPTION: SEARCH SYSCOMMENTS FOR INPUT STRING, OUTPUT NAME OF OBJECT */ /* */ /****************************************************************************/ set nocount on
declare @errnum int , @errors char(1) , @rowcnt int , @output varchar(255)
/****************************************************************************/ /* INPUT DATA VALIDATION */ /****************************************************************************/
/****************************************************************************/ /* M A I N P R O C E S S I N G */ /****************************************************************************/
-- Create temp table to hold results create table #Results ( Name varchar(55), Type varchar(12), DateCreated datetime, ProcLine varchar(4000) )
IF (@ShowReferences = 'N') BEGIN insert into #Results select distinct 'Name' = convert(varchar(55),SO.name), 'Type' = SO.type, crdate, '' from sysobjects SO join syscomments SC on SC.id = SO.id where SC.text like '%' + @string + '%' union select distinct 'Name' = convert(varchar(55),SO.name), 'Type' = SO.type, crdate, '' from sysobjects SO where SO.name like '%' + @string + '%' union select distinct 'Name' = convert(varchar(55),SO.name), 'Type' = SO.type, crdate, '' from sysobjects SO join syscolumns SC on SC.id = SO.ID where SC.name like '%' + @string + '%' order by 2,1 END ELSE BEGIN insert into #Results select 'Name' = convert(varchar(55),SO.name), 'Type' = SO.type, crdate, 'Proc Line' = text from sysobjects SO join syscomments SC on SC.id = SO.id where SC.text like '%' + @string + '%' union select 'Name' = convert(varchar(55),SO.name), 'Type' = SO.type, crdate, 'Proc Line' = '' from sysobjects SO where SO.name like '%' + @string + '%' union select 'Name' = convert(varchar(55),SO.name), 'Type' = SO.type, crdate, 'Proc Line' = '' from sysobjects SO join syscolumns SC on SC.id = SO.ID where SC.name like '%' + @string + '%' order by 2,1 END
IF (@ShowReferences = 'N') BEGIN select Name, 'Type' = Case (Type) when 'P' then 'Procedure' when 'TR' then 'Trigger' when 'X' then 'Xtended Proc' when 'U' then 'Table' when 'C' then 'Check Constraint' when 'D' then 'Default' when 'F' then 'Foreign Key' when 'K' then 'Primary Key' when 'V' then 'View' else Type end, DateCreated from #Results order by 2,1 END ELSE BEGIN select Name, 'Type' = Case (Type) when 'P' then 'Procedure' when 'TR' then 'Trigger' when 'X' then 'Xtended Proc' when 'U' then 'Table' when 'C' then 'Check Constraint' when 'D' then 'Default' when 'F' then 'Foreign Key' when 'K' then 'Primary Key' when 'V' then 'View' else Type end, DateCreated, ProcLine from #Results order by 2,1 END
drop table #Results
GO IF (object_id('sp_FindReferences') IS NOT NULL) PRINT 'Procedure created.' ELSE PRINT 'Procedure NOT created.' GO
My server (SQL 2005 SP2) typically runs with a procedure cache usage of about 92% or higher... lately it seems like at some point in time during the day it just drops to anywhere between 50% and 65%... with this comes horrible server performance and many snowball effects. If I clear the procedure cache it will go up only about 10% for a minute or two. The only way I can get it to recover completely seems to be restarting the SQL service. Then it will be fine till the next incident. The database is a read only (not set to read only but no updates other than replication). and the same SPs are run over and over and over throughout the day. also did notice that the compiles of the SPs goes up drastically at this point also. not sure if this is part of the cause or part of the effect.
CPU is normal. response from anything (even sp_who) is slow.
i do not understand the way procedure cache works completely so I thought I would ask for some direction.
Any ideas where to look or where to start??? Any thing I can do to catch this when it happens would be great.
I have the following:omegalove.comIf you go to the search portion u will notice that there are three dropdownlist that are populate using sqldatasource object.I do not want these two post back. Is there a way we can cache this so it is faster.I would like to learn. I appreciate any help. Please don't give me links. I much rather learn from someone who has hands on.Thank you I will have to separate the code from the ui?--------------------------------------------------------------------- Country:<asp:Image ID="FlagImg" runat="server" Height="12px" Width="20px" />
Im getting this error when trying to set up a cache dependency...are there any special permissions etc?From CS:SqlCacheDependency dep = new SqlCacheDependency("MySite-Cache", "Products");Cache.Insert("Products", de.GetAllProductsList(), dep); From connectionStrings.config:<add name="SiteDB" connectionString="Data Source=localhost,[port]SQLEXPRESS;Integrated Security=true;User Instance=true; AttachDBFileName=|DataDirectory|ASPNETDB.MDF" providerName="System.Data.SqlClient" />Also tried this using my machinename<add name="SiteDB" connectionString="Data Source=<machinename>,[port]SQLEXPRESS;Integrated Security=true;User Instance=true; AttachDBFileName=|DataDirectory|ASPNETDB.MDF" providerName="System.Data.SqlClient" /> From web.config: <caching> <sqlCacheDependency enabled="true" pollTime="10000"> <databases> <add name="MySite-Cache" connectionStringName="SiteDB" pollTime="2000"/> </databases> </sqlCacheDependency> </caching> EDIT: So making progress I can't seem to get the table registered for cache dependency:The sample i have says"aspnet_regsql.exe -E -S .SqlExpress -d aspnetdb -t Customers -et"and the command line response is "Enabling the table for SQL cache dependency..An error has happened. Details of the exception:The table 'Customers' cannot be found in the database."Where does this "Customers" table come from? There is obviously not an application specific "Customers" table in aspnetdb I'm confused probably more by the example than anything....
I have installed SQL Server 2012 Express edition SP1 in my system. I have created a database in the instance. Now when I try to generate scripts of tables using Right click on database > Click on Task > Click on Generate Scripts, it is showing Error in Action 'Getting the list of objects from <database>'.
We are running SQL Server 2012 on Windows 2008 Server. In one database, we would like to create a view which access objects in another database without giving the user permissions to the underlying base tables in the other database. The ownership chain is broken in this case. Can this be accomplished (considering the ownership chain is broken)? If so, what is the easiest method to accomplish this task? Or
Example 1 (Works):
In DB1: --UserA selects from Schema1.View1 (which access tables in DB2).
In DB2: --UserA exists with select permissions on the base tables accessed by Schema1.View1 (in DB1).
Example 2 (trying to accomplish):
In DB1: --UserA selects from Schema1.View1 (which access tables in DB2).
In DB2: --UserA exists (or may not exists) with NO permissions on the base tables accessed by Schema1.View1 (in DB1).
passing serialised objects to a stored procedure for the purpose of data inserts. I see this as being a way to handle multiple row inserts efficiently.
However, in my limited use of XML data I am not so sure how to link the data when I have a dependency on another "object" within the serialised XML.
Below is a code snippet showing what I have so far.
The first insert statement works fine - but how to retrieve the identifier created by the DB - I want to use an SQL statement that finds the record in the table based on the XML representation (of the PluginInfo), allowing me to insert the ConfigurationInfo with the correct reference to the PluginInfo
DECLARE @Config NVARCHAR(MAX) DECLARE @Handle AS INT DECLARE @TransactionCount AS INT SELECT @Config = ' <ConfigurationDirectory > <ConfigurationInfo groupKey="Notifications" sectionKey="App.Customization.PluginInfo"
