MSSQLTREK

Buffer Pool Extension – SQL Server 2014

With SQL Server 2014, Microsoft is bringing a lot of features/enhancements into the wild, one of them is “Buffer Pool Extension” AKA BPE. ( ~~Enterprise edition Only~~). With RTM, MSFT announced that even Standard edition has this feature.

so, what is BPE? The name itself is pretty much self explanatory…It’s an extension for your Buffer pool. yes, with this you can use any non volatile storage device(SSD’s preferred) as an extension for your SQL Server Buffer Pool. Basic idea here is to eliminate requirement of “adding more physical RAM”, Instead you can mount a new Drive and tell SQL Server to treat that newly created drive as Buffer Pool. Sounds very interesting right? But there are few limitations Per Microsoft SQL Server Team’s Blog which we should keep in mind.

Limitations:
Enterprise Only Feature.
Might not be useful for OLAP/DSS Work loads.
Even in OLTP workloads, improvements are very limited for Write-heavy work loads.
If your server got more than 64 GB of RAM, don’t expect much from this.

Personally, for me these limitations are really frustrating. On one hand, this is Enterprise only feature and on the other hand, they are saying don’t expect much from this if your SQL Server has got already more than 64 GB of RAM allocated. What are the chances, any DBA would build a new SQL Server 2014(Enterprise) with less than or equal to 64 Gigs in 2014 or 2015? I would say almost “NIL”.

It Offers:
Performance Gain on Read heavy OLTP Work Loads.

MSFT recommendations: (From SQL Server team Blog post)
Use High throughput SSD for better results.
Start from 4x-10x of the Memory available to SQL Server.

How to Enable BPE :
Step 1:
I’ve created a new Drive(BPE) for this demo purpose as shown below.

Step 2:
Before enabling BPE, Let’s check max memory setting I’ve got on this Instance.(512 MB as shown below)

Step 3:
I’ve tried enabling BPE with 500 MB which actually failed. Reason – Buffer Pool extension size must be larger than current memory allocation threshold.(See below screenshot)

Well, now I increased the size to 600MB and now I got a different Error message(See below)!

Am not sure why this happened, but I’ve created a new Drive (F$) with 2 GB size and it worked this time without any issues as you can see below!!!…I will investigate further why this happened some time later.

Examine from DMV:

How to disable BPE:

Can We alter the size of BPE?
Nope, we can’t. We have to basically disable and recreate it with new size.

Caution: When you disable BPE, chances are….you will get into significant Memory Pressure situation and hence increased IO Pressure.

Bottom line: IMHO, this idea sounds interesting, but I don’t think I would implement this on a production SQL Server considering the limitations it has(YMMV). I would rather convince my management for purchasing real Memory which has no hand cuffs and no limitations!

After all….What are the chances my client doesn’t have money to purchase more DRAM for the sake of true performance boost when they’ve enough money to purchase High Performance SSD’s just for the sake of BPE(which promises me only limited performance gains)? . Remember folks…..now a days physical RAM is very cheap.

Reviewing SQL Server Error Log – A Better approach!

How many of you have a habit of reviewing Error Log(s) of the SQL Server(s) which you support on a daily basis(At least on regular basis, if not daily)? If you are not doing that, go ahead and start making it as a practice from “Right now”. You can thank me later for this suggestion 😀

If you’re already doing that,then you are awesome…! But, let me ask this. How many times you get annoyed reviewing your error log(s), especially if you are looking for a specific error. Well, you can apply filter or you can simply query your error log from T-SQL. But what if you are only looking for all the severe Errors, total error count, Errors by frequency all at one place? Yes, you can write your own query and use SSRS for generating a fancy report. But Wait……What if I say SSMS already has this cool report inbuilt for us?

In this blog post I will show you a better way to decipher your current Error Log for Errors by using that hidden report.
It’s called “Number Of Errors” Report and you can get to this report by right clicking on “Management” Node -> Reports -> Standard Reports->Number of Errors in your SSMS as shown below.

How it looks? See below…

As you can see, at a glance I know I’ve got 6 Severe Errors(Sev 18 or above) and 5 Moderate errors in my current error log. See below screenshots for how neat the info is once I expand those nodes.

Severe Errors:

You can see I’ve got the same 824 Error repeated 6 times. ( Well, I tried attaching the same corrupted ldf file 6 times for this demo)

Moderate Errors:

All errors by Frequency:

Is in’t nice? Personally, I liked this report…and thought of sharing what I’ve discovered with you folks 😀
Please ignore if you are already aware of this nifty report, if not…well, you know it now!

And I gave it a new name & identity…

Hello folks…I am very pleased to announce a brand new name and identity which I’ve given to my blog. It will be http://www.mssqltrek.com from now on.

A brand new Name in brand new year 🙂 Welcome to 2014…

Well, you will be redirected automatically to the new URL even if you visit sqlbuzz.wordpress.com 😀
For feedback and suggestions, please shoot an email to sree@mssqltrek.com.

Thank you – Sree!

SQL Server Discovery Report – Know What SQL components you’ve got Installed at a glance

Let’s assume you’ve got a new SQL Server under your support as a primary DBA and you’ve decided to investigate and document all the SQL Server components/features installed on this Server. What are your options? Will you go to Config manager and look at Services for Installed Services. Well, what about Client components? You can pull build levels/Version(SP/CU) easily for your database engine using T-SQL, what about other services? What about your client tool(s) version…Chances are they will be same as your DB Engine(but they could be different based on how and who patched the SQL Servers)? What if you’ve got multiple Instances of SQL Server with different versions…?

Well, we’ve something called “Installed SQL Server features Discovery Report” under Tools in your Installation Center which provides all this information in a single place 🙂 . Go to the Installation Center from your start->All Programs->Microsoft SQL serverXXXX->Configuration tools->SQL Server Installation Center. Go to Tools and click on discovery report as shown below.

After few seconds, I got below report which gives me basic information on what all I’ve got Installed related to SQL Server on this Server with the build numbers, Edition, clustered/StandAlone etc all at single shot (You can see I’ve got 2 Named Instances, 2008 and 2012) which is pretty useful IMO.

Hope you guys find this nifty tool useful! Cheers…

NATIVE BACKUP ENCRYPTION – SQL SERVER 2014

Microsoft SQL Server 2014 for sure is bringing a lot of cool features/enhancements to aid DBAs and Database Developers….and one of my favorite features it has to offer for a DBA is “Native Database Backup Encryption”.

Till SQL Server 2012:
Let’s say you need to send a backup to Vendor and you want it to be encrypted as per your company security policies. Well, there is no way you can create an encrypted SQL Server database backup natively without help of third party backup tools from vendors like RedGate, Dell, Idera etc. If we don’t have any of those backup tools in our shop, our choice will be pretty much restricted to enabling TDE on the database and take a backup which will be automatically encrypted as well(Unfortunately TDE is Enterprise Edition only feature). What if you are running on standard edition?

Starting SQL Server 2014:
All you’ve to do is select a checkbox while taking a backup(if you are using SSMS GUI) or providing few additional switches in your T-SQL backup statement 🙂
Note: We should create Master Key and Certificate to be able to Encrypt the database backup.

Is this Enterprise Only Feature?
Nope 🙂 You can take Encrypted backups in Enterprise,Business Intelligence and Standard Editions.
Do we need to Turn on TDE at database level?
Nope 🙂
What are the supported Encryption algorithms?
AES_128, AES_192, AES_256, and Triple DES.

So, Now you can Encrypt your database backup in Enterprise,Standard,BI,Developer Editions and an encrypted backup can be restored on any edition(as long as you’ve got certificates 😀 )

Okay folks, now It’s Demo time……I’ve SQL Server 2014 CTP2 Installed in my lab and I created a test database “Tst” for this demo purpose. As of now, it’s a brand new Instance and a brand new database without any keys and certificates.

Step 1:
We’ve to create a Master Key and a Certificate in MASTER Database.(Shown Below)

Step 2: (Am using SSMS for now).
Go to Database Tasks from object Explorer and select backup. In “General” tab , select your database Backup Path and now navigate to “Media Options” tab. This is important…“Backup to existing Media set” is not supported for Encrypted Backups as of SSMS 2014 CTP2. You should select “Backup to a new media set“(Shown below). Am not sure if this intended or Just a bug which will be fixed in RTM.

If not, your encryption section under “Backup Options” tab will be greyed out as you can see in the below screenshot 😦

Step 3:
After selecting your backup path and selecting Backup to new media set, check the Encrypt Backup option in the “Backup Options” tab and select your desired Algorithm and choose the Certificate which we’ve created in Step 1.

Click “OK”. Tadaaaaaaaaaaa……That’s it guys, we’ve created an Encrypted SQL Server Database Backup 🙂

Btw, if you are interested in T-SQL Syntax, here it is…

BACKUP DATABASE [Tst] TO DISK = N'C:\Program Files\Microsoft SQL Server\MSSQL12.MSSQLSERVER\MSSQL\Backup\tst_Encrypt.bak' 
WITH FORMAT, INIT, MEDIADESCRIPTION = N'tst Bak', MEDIANAME = N'Tst bac', 
NAME = N'Tst-Full Database Backup', SKIP, NOREWIND, NOUNLOAD, 
ENCRYPTION(ALGORITHM = AES_256, SERVER CERTIFICATE = [Bcks_Cert]), STATS = 10, CHECKSUM
GO

In the next post let’s see how to restore this encrypted backup.