I have a stored procedure running on SQL Server 2014 with the strangest issue.
The procedure, which is admittedly complex, runs in SSMS in about 2 seconds. It runs as a job under the SQL Agent in at most 2 seconds.
The same stored procedure, when called by a .Net web service, hits a permanent PAGEIOLATCH_SH block and will not run in even 5 or 10 minutes. Even after adding every conceivable index, clearing the cached plans repeatedly, shrinking the log file, clearing disk space, and rebooting the server.
What could possibly account for this behavior?
Related
I have a Job in SQL server which is scheduled to 'Start automatically when SQL Server Agent starts', however, this is creating some issues in our environment. The issue is not SQL specific but because of it we need to delay the execution of this particular job. I cannot schedule this as a recurring job and assign a particular time of a day, it needs to run every time when the SQL Server starts. Is there a way in which I can schedule the job that runs after 15 mins after SQL Server Agent starts?
Sure, just make the first step:
WAITFOR DELAY '00:15:00';
(Or, probably better, you could try to resolve whatever "some issues" are.)
However, note that someone can restart the Agent service without restarting SQL Server; or, they could set SQL Server Agent to not automatically start at startup, so that the next time the SQL Server service is restarted, your procedure will not run.
If you want to tie some startup activity to SQL Server starting, you could probably look into startup procedures, but if you need it to wait 15 minutes, the first thing in the procedure would be the above WAITFOR. Also startup procedures can't have input parameters (or output parameters, but that is less likely to be an issue for a stored procedure you're calling from a job).
Finally, SQL Server 2008 R2? That was barely still in support at the beginning of the last decade.
I have 5 stored procedures, called by an api, that run in under 100 ms normally, but intermittently, all the stored procedures suddenly take > 10 seconds in production. We did stress test before going live and it was all good during stress test.
For each of the stored procedures, I capture start time using SYSDATETIME() and log it an table at the end of the stored procedure with end time as well. So I run profiler on production and notice strange things.
For example, today, profiler RPC:completed event start time is 09:18:04.680 where as my stored procedure execution log tables says the execution started at 09:19:54.288. So there is a 110second mismatch between profiler execution start vs my stored procedure internal start time. So this happens to all stored procedures for a window of 2-3mins and everything clears by itself.
I've ran perfmon and nothing shows out of ordinary to me. The SQL Server has high capacity with the application only running few users currently so not a very high traffic application.
I also have Redgate SQL Monitor and it doesn't show any abnormal wait times.
I'm not even sure where to look for. I'm not sure its parameter sniffing because one of the stored procedure affected doesn't accept any parameters. After the 2-3 minutes all the stored procedures run as expected.
Currently running SQL Server 2008 R2 SP1 on 64-Bit Windows Server 2008 R2 Enterprise on a Intel dual 8-core processor server with 128 GB RAM and 1TB internal SCSI drive.
Server has been running our Data Warehouse and Analysis Services packages since 2011. This server and SQL instance is not used for OLTP.
Suddenly and without warning, all of the jobs that call SSIS packages that build the data warehouse tables (using Stored Procedures) are failing with "Deadlock on communication buffer" errors. The SP that generates the error within the package is different each time the process is run.
However, the jobs will run fine if SQL Server Profiler is running to trace at the time that the jobs are initiated.
This initially occured on our Development server (same configuration) in June. Contact with Microsoft identified Disk I/O issues, and suggested setting MaxDOP = 8, which has mitigated the deadlock issue, but introduced an issue where the processes can take up to 3 times longer at random intervals.
This just occurred today on our Production server. MaxDOP is currently set to zero. There have been no changes to OS, SQL Server or the SSIS packages in the past month. The jobs ran fine overnight on September 5th, but failed with the errors overnight last night (September 6th) and continue to fail on any retry.
The length of time that any one job will run before failing is not consisent nor is there consistency between jobs. Jobs that take 2 minutes to run to completion previously will fail in seconds, where jobs that normally take 2 hours may run anywhere from 30 - 90 minutes before failing.
Have you considered changing the isoloation level of the database. This can help when parallel reads and writes are happening on the database.
I am executing a stored procedure using SQL Server Agent Job in SQL Server 2005.
This job was running fast until yesterday. Since yesterday this job is taking more than 1 hour instead of 2 mins.
I executed the stored procedure in SSMS, it just took less than 1 minute to execute.
I could not figure out why it is taking more than 1 hour when executed as a SQL Server Agent job?
After some time commenting and assuming that the SP performs with the same input parameters and data well when executed in SSMS, I finnaly think I can give a last tip:
Depending on what actions are performed within the SP (e.g. inserting/updating/deleting a lot of data within a loop or cursor), you should set nocount on at the beginning of your code.
set nocount on
If this is not the case or does not help, please add more information, already mentioned in the comments (e.g. all settings of the Job and each Jobstep, what has been logged, what is in the Jobhistory, check SQLerrorlogs, eventlogs,....).
Also take a look at the "SQL Server Logs" maybe you can gather some info here. Also a look into the Application/System eventlo of the Databaseserver is always a good idea.
To get a basic overview you can use the Activitymonitor in SSMS, by selecting the Databaseserver and selecting "Activity monitor" from contextmenu and search for the sql agent.
My last try would be to try to run a sql trace for the agent. In this case you would start a trace and filter e.g. by the user that the SQLAgent Service runs. There are so many options you can set for traces, so I would recommend to google for it, search on MSDN or ask another question here on stackoverflow.
We have a large proc that runs in 88 seconds in SSMS and 30-45 minutes in SQL Server Agent. I added the dbo. prefix on all the table names and now it runs just as fast as SSMS.
I've noticed that SQL Agent jobs ignore the server's MAXDOP setting and run everything with a MAXDOP of 1. If I run a stored procedure in a query windows, it obeys the server settings and uses 4 processes. If I use SQL Agent, any stored procedure I run uses only one process.
I have a similar issue with a script that calls a number of UDFs that I created. The UDF's themselves normally run subsecond under SSMS. Likewise, running the reports I generate with them is bearable under SSMS (30d data in 8s, 365d data in 22s). I've always done NOCOUNT ON with my SQL Agent jobs as they normally generate text files out for pickin up by other processes or Excel and I do not want the extra data at the end, so it was not a solution for me.
In this case, when we run the exact same script under SQL Agent as a job, my times grow exponentially. My 8s script takes 2m30s and my 22s script takes 2h20m. This is the same whether I run it midday with other user activity and jobs or after hours with no user activity, nor jobs or backups running. Our server is idle and at best I get one of the 8 cores being utilized when run. DB is only about 10GB running on SSD with a cached RAID card and 16 of 32GB RAM is free. Since my SQL runs efficiently in SSMS, I am pretty well of the belief that I am hitting a threading limit of some sort. I have researched and tried adjusting MAXDOP just prior to the scripts in the SQL Agent with no luck.
Since this is an activity I want to schedule, it needs to be automated one way or another. I could let these scripts take the hours they need to run as SQL steps in SQL Agent jobs, but I decided to run from command line instead and I get the same performance I see in SSMS.
sqlcmd -S SQLSRVRHost -i "C:\My Script Loc With Spaces.sql" -v MyVar="VarValue" >"C:\MyOutputFile.txt"
So I created a batch script with the SQL jobs run from sqlcmd. Then I run the batch script from a SQL Agent job, so I still have the same management and control in place. My 4 SQL jobs that collectively took over 3 hours to run complete in 1 min and a few seconds from a single batch script executed by SQL Agent.
I hope this helps...
Stored procedures are compiled on first use.
There are options to clear cache:
DBCC FREEPROCCACHE
DBCC DROPCLEANBUFFERS
--To Verify whether the cache is emptied
--DBCC PROCCACHE
or to recompile or to reduce recompilations.
But is it possible to force frequently used stored procedures' execution plans be pre-cached and stay in memory?
I know how to do it in ADO.NET, i.e. from outside of SQL Server, but this question is how to do inside SQL Server - to be launched with the start of SQL Server itself.
(*) For example, I see in SSMS Activity Monitor a running process (Task State: RUNNING, Command: SELECT) that is continuously executing T-SQL (according to Profiler) in context of tempdb database though SQL Server Agent is disabled and SQL Server is not loaded by anything, see "Details of session 54" in "Where are all those SQL Server sessions from?".
How would I do the similar resident process (or, rather, auto-starting by SQL Server start service or session) periodically recycling stored procedure?
Related question:
Stored procedure executes slowly on first run
Update:
Might be I should have forked this question in 2 but my main curiosity is how to have periodic/ looping activity with SQL Server Agent disabled?
How was it made with mentioned above RUNNING SELECT session (*)?
Update2:
Frequently I observe considerable delays while executing stored procedures querying very small amount of data which cannot be explained only through necessity to read huge amounts of data.
Can we consider this - considerable delays on insignificantly small data - as context of this question?
Just execute it from a script. You could do this after any sql server restart. If they are frequently used, it shouldn't be much of a problem after that.
Seems like this question eventually got answered in:
Can I get SQL Server to call a stored proc every n seconds?
Update: These tips will do the trick:
Keeping data available in the SQL Server data cache with PINTABLE
Automatically Running Stored Procedures at SQL Server Startup