I am sure I have seen in the past in a monitoring tool that PLE drops off to 0 whenever we do a backup. I was doing some reading around this however and found something that said backups use a different portion of memory external to the buffer pool (minmax settings).
Is this correct and how can I tell how much memory will be required for a backup?
Hi, I'm trying to chase down some bottlenecks, and am currently tyring to figure out what's actually in our data buffer pool.
We've recently upgraded to SQL Server 2005 (sp2a); there's 4GB memory on the box (an active/passive cluster) with the /3GB switch set. I'm working on the learning curve for
sys.dm_os_buffer_descriptors and sys.allocation_units [and boy I sure wish SSMS's query windows wouldn't "copy" in HTML]. Based on BOL and some poking around, I've come up with the following query to list pages used within a given database:
SELECT
count(*) cached_pages_count
,isnull(obj.name, '<unidentified object>') TableName
,obj.index_id
,ind.name
from sys.dm_os_buffer_descriptors bd
left outer join (select
object_name(object_id) name
,object_id
,index_id
,allocation_unit_id
from sys.allocation_units au
inner join sys.partitions p
on au.container_id = p.partition_id -- 2005 compatible, but maybe not in future versions
) obj
on bd.allocation_unit_id = obj.allocation_unit_id
left outer join sys.indexes ind
on ind.object_id = obj.object_id
and ind.index_id = obj.index_id
where bd.database_id = db_id()
group by obj.name, obj.object_id, obj.index_id, ind.name
order by cached_pages_count desc
This would appear to list how many pages are sitting in our buffer pool for which objects for the currently selected database. The thing is, for our "main" database, the vast majority of pages fall in that "unidentified" bucket -- their allocation_unit_ids are not in sys.allocation_units (or tempdb, I checked there just in case).
My question is: what are these pages? Where is this data coming from? Might these somehow be related with our execution/query cache, which appears to be larger than our data cache?
As may be obvious, this is all new to me, and any help would be greatly appreciated!
t
I am reading about Buffer Pool Extensions, and how it stores data pages on media like an SSD, to speed up retrieval in future. Would this be useless if my mdf files are already on SSD media? At most, I envisage it meaning that instead of grabbing the data from the mdf, it would grab the data from the buffer pool extension drive, but if they are both on SSD's, I'm not sure of how much return I would see.
Has any user decided to use BPE when their data is already on SSD's, and have they noticed any improvement in these cases?
Extending the buffer pool onto an SSD drive that is shared ? For instance, if we had a mirrored system drive(The C logical partition) on SSD's, can we use the remaining space on that mirrored partition to extend my SQL 2014 buffer pool ? I understand that in this scenario, there is some competition for the I/O throughput between SQL Server's extended buffer pool and the OS. We intend to have the pagefile on a different disk, other than this specific SSD.Â
View 11 Replies View Relatedextending the buffer pool onto an SSD drive that is shared ? For instance, if we had a mirrored system drive(The C logical partition) on SSD's, can we use the remaining space on that mirrored partition to extend my SQL 2014 buffer pool ? I understand that in this scenario, there is some competition for the I/O throughput between SQL Server's extended buffer pool and the OS. We intend to have the pagefile on a different disk, other than this specific SSD.
View 1 Replies View RelatedHello:
I tried to synchronize the SQL 2000 database with the SQL mobile server on PDA with SQL server management studio from SQL 2005. I got the error as €œThe buffer pool is too small or there are too many open cursors. HRESULT 0x80004005 (25101) €?. The SQL database file size is 120MB.
I create the .sdf file on PDA with the following C# code:
string connString = "Data Source='Test.sdf'; max database size = 400; max buffer size = 10000;";
SqlCeEngine engine = new SqlCeEngine(connString);
engine.CreateDatabase();
I think the 400MB max database size and 10000KB max buffer size are big enough to hold that SQL database data and I have already successfully synchronized my PDA with another smaller SQL server database file. I have been kept trying and searching this for couple of days and still can not figure it out.
Moreover, the synchronization always stops at the same table.
Please help and a lot of thanks in advance.
How do i check the size of the datacache allocated from the buffer pool by sql server?
DMV or anything to show me the pool allocation sizes for the various pools in sql server i think i may be able to work from there.
I am working with merge replication. The db server is running Windows 2003 Server Std x64 with SQL 2005 Std x64. The IIS server is running Windows 2003 Server Stx x86. The clients are Windows Mobile 5.0 running SQL 2005 Mobile.
I have previously been able to get the test client to initialize a subscription to the publication. I made some changes recently and added about 7 tables, bringing the total articles to 104. Some of the articles have unpublished columns, which means they are using vertical filtering as well. This publication is also using parameterized filters. During publication creation, there are several warnings that "Warning: column 'rowguid' already exists in the vertical partition".
The snapshot agent runs without any errors. When the client attempts to initialize, I get the error "The buffer pool is too small or there are too many open cursors."
My question is 2 part. First, what is causing this error, and second, how can it be resolved?
hi i'm having this error on my application"cannot allocate more connection.connect pool is at maximum increase max pool size" the proble is when i do testing this error does not apply it only Appears when the application is been used by many people
How can I resolve this?
Thanks
How to find max pool size in sql server 2012?
View 2 Replies View RelatedWe have a multi-site AG and are demoting one of the remote sites out of the AG. In doing so, we've discovered that no logic exists to remove an IP address from the listener.
It seems that the ALTER AVAILABILITY GROUP MODIFY LISTENER logic lacks functionality other than ADD. [URL] ....
I'm afraid to just remove the IP address from the cluster object as that IP is also stored in the HADR systables.
select * from sys.availability_group_listener_ip_addresses
select * from sys.availability_group_listeners
Last Sunday on our Primary server I saw some blocking and the First spid that blocked everything was waiting on LogBuffer wait. At that time the server was not running hot and our DB is on SSD's. There was no memory pressure(1 TB of memory on the server) It is strange why we should get LogBuffer wait when we are running on the fastest disks possible and there was not much action going on the DB.
View 4 Replies View RelatedWhat does this error message imply?
View 3 Replies View RelatedWhat is better values for Buffer Cache Hot Ratio in SQL Server 2012. Is the values changed from 2008r2 to 2012?
View 2 Replies View RelatedWe 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 am using SQL 2012 and I am trying to find buffer cache usage by DB objects within a particular DB.
I am running the following query
select
name as DB,
objname as db_object_name,
COUNT(name) as cache_page_count,
COUNT('x')*8.0/1024 as size_mb
[Code] ....
Following are the results:-
DB db_object_name cache_page_countsize_mb
TEST_DBNULL 428 3.34375
TEST_DBsysobjvalues 369 2.882812
TEST_DBsyscolpars 44 0.34375
TEST_DBsysssislog 38 0.296875
....
.....
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.
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.
I encountered the following error while attempting to preview an RDL report I was developing in VS2010 using SSDT:"The size necessary to buffer the XML content exceeded the buffer quota"
View 3 Replies View RelatedWe have a set of reports with same header section in all the reports. So while developing a new report i used to copy that header section to the new report with same dataset names (without any change) , but while rendering the report it is throwing error " The size necessary to buffer the XML content exceeded the buffer quota".
View 2 Replies View RelatedHi
I have a master package that executes a series of sub packages run from a SQL Agent job. One of those sub packages has been stable for a week, running at least once per day, but it just failed despite having been run once already today with the same set of input data.
There were a series of errors showing in the event log for the Execute Package Task starting with "Buffer Type 15 had a size of 0 bytes.", then "The buffer manager failed to create a new buffer type.", then "The Data Flow task cannot register a buffer type. The type had 32 columns and was for execution tree 3.", then "The layout failed validation." and finally "Error 0xC0012050 while loading package file "C:[Package].dtsx". Package failed validation from the ExecutePackage task. The package cannot run.".
SQLIS.com reports the constant for the error code as DTS_E_REMOTEPACKAGEVALIDATION ( http://wiki.sqlis.com/default.aspx/SQLISWiki/0xC0012050.html ).
I then ran the package on my dev machine in BIDS and it worked fine, so I re-ran the job on the server and this time that package executed ok, but another one fell over but did not put anything in the event log.
Does any one have any idea what happened?
TIA . . . Ed
Our server administrator forwarded some messages from SCOM that indicate:
SQL DB Engine 2012 Page Life Expectancy and Buffer Cache Hit Ratio is too low
When I logged into the offending server, I could not find anything in the SQL Log File that indicates this.
I was wondering how did SCOM identify this issue - where in SQL Server would this have been reported to SCOM?
Good day everyone,
I'm experiencing a completely random warning from any given row count component within any given data flow task. It occurs sporadically. Whilst distracting, I don't see any adverse effects to the data after the packages complete. Can someone weigh in on this warning and let me know if it is indeed benign or what I maybe able to do to fix it?
Here's the warning:
"A call to the ProcessInput method for input 75997 on component "CNT Rows sent for STG table" (75995) unexpectedly kept a reference to the buffer it was passed. The refcount on that buffer was 4 before the call, and 5 after the call returned."
Thanks,
Langston
I am setting up mirroring on one of our live databases tonight. The database is quite big, around 300GB.
At the moment we are doing log backups once a day and full backups every night.
My question is, when I set up the mirror, will the log backups on my Principle DB affect the mirror in anyway?
I have inherited a new SQL Server 2008 database server and can not figure out how my user databases are being backed up. This database server is running under a VM.
All the user databases are being backed up nightly per the SQL server log. The backups are written to a virtual disk and is kicked off by the NT AUTHORITYSYSTEM user. I can not see the virtual disk. A restore task does not provide any information about the last backup. I have created a new database, and it is automatically included in the next set of backups.
I have looked at the windows event viewer with out any luck. There are no SQL Server Maintenance Plans or Agent jobs that call a backup. I have also checked the Windows Task Scheduler and can not find any task that does a backup.Could the backups be called from another server ?
I am using Ola Hallegren's scripts to do backups. He uses @Cleanup Time to delete backups older than a certain number of hours. My situation is I do a full backup of a database on Sunday and then I have a few Differentials and then log backups for the rest of the week. When Sunday rolls around again and my full backup is finished, I would like to delete all the differential backups and log backups. Any way that I could accomplish this using Ola's scripts?
View 1 Replies View RelatedI have tried doing sql server backups to a file share and that has been taking too long. So I've decided to backup locally and then taking those backups and getting them off the server. For those that are doing this what do you use to get your backups off the server?
View 9 Replies View RelatedJust hit a issue where we had a 40gb backup file for a database with an mdf of less than 2gb and tran log less than half a gb.
Noticed someone had set the backup for this database to append the backup file in stead of overwrite it.
Just wondering why would you want to append a backup instead of overwrite it?
I just completed a copy-Only compressed backup of a DB (with a FULL Recovery Model ) on SQL Server 2012 and the resulting backup (the bak file) is 1/100th the size of the data & log file. Is the compression in SQL Server 2012 just that good or did something else happen that I did not catch? Below is the T-SQL to re-create the backup. The size of the data file is 750MB and the log file is 75GB and is %95 used according to the SQLPERF command.
Does the compression in SQL Server 2012 simply that good
BACKUP DATABASE [MYBIGOLEDB] TO DISK = N'Z:Microsoft SQL ServerMSSQL11.MSSQLSERVERMSSQLBackupMYBIGOLEDB_20150611.bak' WITH COPY_ONLY, NOFORMAT, INIT, NAME = N'MYBIGOLEDB-Full Database Backup', SKIP, NOREWIND, NOUNLOAD, COMPRESSION, STATS = 10
GO
Getting "The specified network name is no longer available" during SQL Backups dumping to Network share.
- problem started occurring on July 3, 2015
- our Ola Hallengren backup solution deployed to over 150 SQL Servers.. was running fine for almost 2 years
- Occurring in multiple SQL Server environments: W/Server 2012 Ent, W/Server 2008 Ent, SQL 2012 Ent, SQL 2008 R2 Ent
- We're utilizing latest Ola Hallengren backup solution (Jan 2015 release)
- Dumping to network share (jobs running under SQL Agent account w/ local admin & sysadmin on server and full rights to Network Share
So I'm testing some things in our new servers and was trying to restore a database from some striped backup sets. We have 4 files for our backups and restoring the FULL backups with no recovery worked beautifully via SSMS. But when I tried to restore the differentials (also striped across 4 files), the GUI gave me this error:
Unable to create restore plan due to break in the LSN chain.
How to locate when the break happened and I came across this article about how this is an SSMS 2012 bug.
So I tried the advice in this article to attempt a restore via Files and Filegroups, and ended up with the below error:
EDIT: Picture is attached if it is not showing in post.
I was able to restore via T-SQL, but I want to also be able to restore through the GUI.
We have a SQL 2012 server instance that has log shipping set up to another SQL 2012 server to provide a warm standby for a forward facing application. The databases on the primary server occasionally are required to be backed up and restored to a development environment, completely different server. Is there a way to schedule full backups with log shipping enabled?
View 2 Replies View RelatedNative backups to NAS do not complete.We have been experiencing an issue whereby our native backups are hanging with status': SUSPENDED/ RUNNABLE...I ran select * from sys.sysprocesses. All of the backup SPIDs processes show BACKUPTHREAD/PREEMPTIVE_OS_FILEOPS
This first occurred last Wednesday evening. When I discovered this on Thursday, I attempted to kill the backup jobs. This also hung with 0% completed/0% time remaining. Backups hung on more than one instance.That evening, I attempted to restart the instance which also failed with something along the lines of: could not start MASTER file in use.
I then restarted the server--which I really did not want to do--and this cleared it. I was also able to manually kick off maintenance plans (DBCC CHECKDB and full backup) without issue.I was off Friday and the weekend. I came in this morning and found the maintenance plans (diff/tlog backups) did not complete in some of the instances--in one case, the instance affected now was not affected before. They appeared to have hung on their next scheduled kickoff which was later that night after I went home
Remembering the "file in use" error, I have run process monitor to see if anything unusual had a lock on any files. I saw only SQL Server and Double-Take processes accessing log files.Being a relatively new DBA, I am user where to go next in trying to track down the cause of this issue. This is fairly urgent as one of the instances that has had this problem both times is our production SharePoint environment.
ENVIRONMENT:
SQL version:
Microsoft SQL Server 2012 (SP1) - 11.0.3368.0 (X64)
May 22 2013 17:10:44
Copyright (c) Microsoft Corporation
Enterprise Edition: Core-based Licensing (64-bit) on Windows NT 6.2 <X64> (Build 9200: )