I will be doing some performance testing on financial application next
month. Without going into a lot of details, I suspect I will have a
potential bottleneck when writing to the log file.
My hardware setup is a quad 2.8 Xeon Dell server direct attached to a
DELL/EMC CX200 (Fibre channel array with 10 X 30something GB, 15,000
rpm drives, with about 1GB of memory on the array for caching.
This is a benchmark environment, so I am not concerned about loosing
data. I am looking for a little guidance on using raid (0 or 10)
and/or file groups to spread IO to db objects (log file(s), data,
indexes, tempdb, etc). I have read about and played with file groups
enough to know that SQL server does some level of load balancing
across file, but am unclear it is in parallel or serialized.
Common wisdom seems to be to separate data, non-clustered index, logs,
and tempdb onto separate files, but I am unclear on how to make best
use of the high-speed disk array. I'd greatly appreciate opinions on
which would perform better; one file on a stripe set of N drives (raid
0 or 10), N files in a file group placed on N (non-striped) drives, or
a combination of the two? Is the answer the same for both log and data
(or index) files?
We are having a conversation at work and the subject of load balancing with SQL came up. Right now we are running SQL Server 2014 on four (4) machines. I am using a AlwaysOn with Availability Groups (AG). Now I know that we can scale out the reading in AG by allowing the secondary serves to receive reads.
Is there a way to be able to do this with writes? Can I have in essences 2 masters that some how reconcile with each other? We are expecting a huge amount of writes in the near future and we need a way for SQL to handle the amount of traffic we are expecting with out any issues.
I explored the possibility of Peer - to - Peer replication; however, it seems that it would be more work if we are constantly making updates to the database scheme.
I am configuring a new database server, without SAN access, and want to know what is the best practice for SCSI RAID configuration. Do most folks prefer RAID 5 or RAID 10 configurations where their databases will reside?
A little background on what I am trying to achieve first. We are moving to Azure virtual machines and we will have 8 disks on the SQL Server box. I am adding more files to the primary file group and each file will go on its own drive. I am then rebalancing data across these files by rebuilding all of the indexes on the tables which is working fine. No problems so far all is good.
I now have an additional problem. If there is a lob or blob column on the table, rebuilding the clustered index and all the non clustered indexes doesn't rebalance the blob or lob data across the disks such as it does with in row data.
I cannot find any articles on rebalancing lob or blob data because all the articles say to move to a new file group. I do not want a new file group, I just want to use the primary file group where the data already resides, and just redistribute it evenly in the same way that I can in row data which is working fine.
One solution I thought about was to BCP data out of the table, truncate the table and then BCP back into the table which I imagine would have the desired effect of distributing the data evenly over the files.
I have one of our production Accounting Databases starting from 2 GBnow grown into a 20 GB Database over the period of a few years...I have been getting timeouts when transactions are trying to updatedifferent tables in the database.. Most of the error I get are I/Orequests to the data file (Data file of the production dbAccounting_Data.MDF).I would like to implement the following to this Accounting database.I need to split the Data file into multiple files by placing some ofthe tables in different file groups. I have the server upgraded to beable to have different drives in different channels. I can place thesedata and log files in different drives so it will be less I/Oconflicts..I would like to have the following file groups..FileGroup 1 - which will have all database definitions (DDL).FileGroup 2 - I will have the AR Module tables under here..FileGroup 3 - I will have the GL module tables under here..FileGroup 4 - I will have the rest of the tables under hereFileGroup 5 - I will like to place the indexes under here....Also where will the associated transaction files go?I would like to get some help doing this. Is there any articles / helpavailable that I can refer to. Any suggestions / corrections/criticisms to what I have mentioned above is much appreciated...!Thanks in advance....
RAID 5 beats RAID 10Can I get some feedback on these results? We were having some seriousIO issues according to PerfMon so I really pushed for RAID 10. Theresults are not what I expected.I have 2 identical servers.Hardware:PowerEdge 28502 dual core dual core Xeon 2800 MHz4GB RAMController Cards: Perc4/DC (2 arrays), Perc4e/Di (1 array)PowerVault 220SEach Array consisted of 6-300 GB drives.Server 1 = Raid 103, 6-disk arraysServer 2 = Raid 5 (~838 GB each)3, 6-disk arrays (~1360 GB each)TestWinner% FasterSQL Server - UpdateRAID 513Heavy ETLRAID 516SQLIO - Rand WriteRAID 1040SQLIO - Rand ReadRAID 1030SQLIO - Seq WriteRAID 515SQLIO - Seq ReadRAID 5MixedDisktt - Seq WriteRAID 518Disktt - Seq ReadRAID 52000Disktt - Rand ReadRAID 562Pass Mark - mixedRAID 10VariesPass Mark -Simulate SQL ServerRAID 51%I have much more detail than this if anyone is interested.
I am looking to find out when to use file groups when backing up. When should you use this, what's the benefit over just doing a full db backup? Is it better when you are dealing with large db's?
Also this question has been on my mind for a while. Why shouldn't you shrink the db after every full backup? What is the negative in doing so?
Hi everyone, While creating our database in only one disc(C or D), suppose that we create more than one file group in order to group our data files. However, in this situation; I wonder that whether it brings any benefit or advantage to us.
Also, I wonder that why we always have to put our data file into separate file group if we use separate discs for data files. Is not it allowed to use only one file group even if we use separate dics ?
I had a database that’s comprised of different file groups and log files spread out among different hard drives. I have recently upgraded the database to SQL 7.0 on a RAID 10 volume. I would like to consolidate all the file groups and files as well as various log files into one primary datafile and logfile. How do I do that? Thanks in advance.
I am currently converting some Oracle scripts to SQL Server. Encountered this following code segment in a CREATE TABLE query :
CONSTRAINT ck_PK PRIMARY KEY ( O_ID) USING INDEX TABLESPACE DIRECT PCTFREE 10 STORAGE ( INITIAL 65536)) TABLESPACE DIRECT PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 STORAGE ( INITIAL 65536 MINEXTENTS 1 MAXEXTENTS 2147483645 FREELISTS 1 FREELIST GROUPS 1)
what is the equivalent conversion in SQL Server. Is it just ON PRIMARY in the PRIMARY KEY clause ?? Are the Segments and Extents in Oracle equivalent to Filegroups in SQL Server.
Something strange.I have a database(SQL2000) with two file group(on seperate physicaldrives).One is meant for table data[PRIMARY] and one for indexes [INDEX].So i create a table on the [PRIMARY] file group, and fill indata.Next I build a clustered index on the table, on the [INDEX] filegroup.Once the index is built, the database now indicates that the filegroupfor the table [INDEX]! and not [PRIMARY] as i originally set it up for!My question it then: Has the table been moved or is this somehow anerror in SQL server?I would really appreciate any thought anyone might have on this?
I am looking for the easiest way of rebalancing data across multiple files.
Instead of creating a secondary filegroup and then dropping and recreating all indexes in the database which is going to take ages (we have a lot of tables and indexes), I am trying to just add more files to the primary file group and then rebalance data evenly between these.
I guessed that adding the new files to the primary file group and then rebuilding all indexes on a table should redistribute the table over these multiple file groups evenly. This is not the case though. It does rebalance data a bit but I still end up with the majority on the first file that existed.
I have attached the script I am running, maybe it is something in the create database/file statements that is the issue.
Basically what I am seeing is to start off with the table is 160MB. I then add the file groups and rebuild all indexes on the table. The first file is then about 100MB and each of the three other files are about 20MB. I would expect them all to be the same size.
We have a large Datawarehouse and the size is 50TB.. The tables are placed in filegroups based on the schema like fact, dimensions, raw data each sit on seperate filegroups. I am thinking will it make sense to seperate the large facts which are having billions of rows so that they reside on filegroups on their own..
I am facing a peculier problem. Problem definition goes like this,
I have one staging DB in which all the tables resides in Primary file and one production DB in which tables resides in 2 secondary files.
Now when iam trying to load the data from the table A in staging which is on primary file to the table A1 in production DB which in secondary file, all the data are going to error log instead of table A1.
We have recently added a new file group and file on a new drive. We have tested it by moving a small table to the new file group. We would like to relocate a new table to this file group but the table is about (we estimate) 75GB. My question is this: How long can we expect the transfer of data from the current file group to the new one for this table? I understand that depending on our hardware the answer may vary but does anyone have a rough estimate?
The current current (primary) file is located on a DELL SAN and the new secondary group is on a EMC 4700 both are connected via fiber channel.
Also a bonus question would be: Does a "normal" database backup created as a maintenance plan backup the seconary data as well into the BAK file?
I am building partitiong tables, partitioning on different file groups:
the question is:
Partitioned table referred to old data that are not frequent accessed for reporting can be stored on separate location(External storage, tape and so on) or to make partitioning functioning must all file groups must be presents?
If not, how can I separate old data from current ones (still using partitioning) to reduce the size of DB?
What it is the best for storage data and easy to access it when needs arise (eg reporting): Tape, external storage, others?
I have a new SQL 2005 (SP2) Reporting Services server to which I've just upgraded and deployed some SSRS 2000 reports.
I have a subreport that contains a matrix with two groups. The report data seems to be inexplicably repeating the data for the first row in the group for all rows in the group. Example:
ID1 ID2 DisplayData
1 1 A
1 2 B
1 3 C
2 1 A
2 2 B
2 3 C
Parent group is on ID1, child group is on ID2, report would show:
1 1 A
2 A
3 A
2 1 A
2 A
3 A
Is this a matrix bug in 2005 SP2, or do I need to do something differently? I can no longer pull a comparison version from an SSRS 2000 server to verify, but I believe it was working as expected before...
When the database is configured for mirroring and you want to do partitioning on that database, How can we do? Is this similar process or any variation there while adding file groups and files? The partition will reflect in the mirroring database also?
is there a way to restore all file groups except one? example: Database A has 10 filegroups, but 1 of them is defunct, so i cant delete it and there's no backup for restore it.Can I create a new DB restoring the 9 good FGs from a database A's backup?
We are in the process of replacing our primary production server. In the process of determining how SQL server is going to be structured, it has been suggested that I place all current and new indexes on a separate file group. These filegroups would then reside on a separate shelf on the server. What are the pros and cons of doing this?
- 500 GB DW - 5 GB in smaller DBs - 220 GB TempDB - 350 GB in Log files.
My machine is Fujitsu Primergy 64 cores (with HT) and 192 GB RAM.
I have several IO locations:
- 540 GB in-server HDD 15k RAID10 - 1 TB HDD 15k RAID10 on SAN (separete controller) - 2 TB HDD 15k RAID10 on SAN (same controlller as below) - 800GB SSD RAID10 on SAN (same controller as above)
Data warehouse has 2 fact tables that are absolutely crucial and quite large.
Now i want to organize DB into several Filegroups and put them on different drives. Filegroups I'm thinking of:
- FILEGROUP1: for 1st crucial Fact Table - FILEGROUP2: for 2nd crucial Fact Table - FILEGROUP3: for tempDB - FILEGROUP4: for dimensions data - FILEGROUP5: for the rest of facts data - FILEGROUP6: for dimensions indexes - FILEGROUP7: for the rest of facts indexes - FILEGROUP8: for 1 log file of one smaller DB (its in full-recovery and its quite large) - FILEGROUP9: for the rest of log files - FILEGROUP10: others
How should I organize them across available drives? I was thinking about sth like:
I know that having multiple filegroups on the same drive is pointless regarding performance, but in future i could actually add some more drives, so i want to separate them now.
Also - how much files per filegroups should i create? Considering 1 or 2. Except TempDB where I am going for 4.
We have a set of databases some are fully read-only others have read-only file groups, is there any way to restore backups of these taken on an MSDE 2000 to an SQL Express 2005 instance?
When doing the inplace upgrade we change these to read-write before the upgrade and set them back after the upgrade.
These databases are used in the field by customers althought the controlled upgrade requires a backup before (and blocks if it fails) and tries a backup after if the post upgrade backup fails (due to disk space) we might need to recover from this odd situation.
The only solution I have is install MSDE some place restore to this then do the controlled upgrade again, any other ideas?
How is load balancing working in SQL Server 2000. We want to have two different servers as a back end for our web based eCommerce application. Is this possible? While there be any modification requirement in the application?
What is the meaning of Loadbalancing and how can I use this term to my advantage. Q2. How would I know that I need to do load balancing and how can I set it up.
I have wrote load balancing in BOL and did not get any thing on it. can anyone refer me to where I can read more about it.
We have a Intranet Application which uses IIS / SQL Server 7.0, we are trying to support the application for 30,000 + users.
Since SQL Server can only support upto 32676 user connections (Theoretically), is it possible achieve this with clustering / dynamic load balancing. Does MSCS and SQL 7.0 support this. Any other ideas, 3rd party software etc?????
How much traffic/load can a database server running MS SQL server takebefore it can't handle it anymore? And when that time comes, what are therecourses? Am I able to load balance it between separate servers?
