In the last two days, I’ve been part of two discussions, one of which was about the need to run CHECKDB on modern storage (yes, the answer is always yes, and twice on Sundays), and then another about problems with third party backup utilities. Both of these discussions were born out of (at the end of the day) infrastructure teams wanting to treat database servers like web, application, and file servers, and have one tool to manage them all. Sadly, the world isn’t that simple, and database servers (I’m writing this generically, because I’ve seen this issue crop up with both Oracle and SQL Server). Here’s how it happens, invariably your infrastructure team has moved to a new storage product, or bought an add on for a virtualization platform, that will meet all of their needs. In one place, with one tool.
So what’s the problem with this? As a DBA you lose visibility into the solution. Your backups are no longer .bak and .trn files, instead, they are off in some mystical repository. You have to learn a new tool, to do the most critical part of your job (recovering data), and maybe you don’t have the control over your backups that you might otherwise have. Want to stripe backups across multiple files for speed? Can’t do that. Want to do more granular recovery? There’s no option in the tool for that. Or my favorite one—want to do page level recovery? Good luck getting that from a infrastructure backup tool. I’m not saying all 3rd party backup tools are bad—if you buy one from a database specific vendor like RedGate, Idera, or Quest, you can get value-added features in conjunction with your native ones.
BTW, just an FYI, if you are using a 3rd party backup tool, and something goes terribly sideways, don’t bother calling Microsoft CSS, as they will direct you to the vendor of that software, since they don’t have the wherewithal to support solutions they didn’t write.
Most of the bad tools I’m referring to, operate at the storage layer by taking VSS snapshots of the database after quickly freezing the I/O. In the best cases, this is non-consequential, Microsoft let’s you do it in Azure (in fact it’s a way to get instant file initialization on a transaction log file, I’ll write about that next week). However, in some cases these tools can have faults, or take too long to complete a snapshot, and that can do things like cause an availability group to failover, or in the worst case, corrupt the underlying database, while taking a backup, which is pretty ironic.
While snapshot backups can be a good thing for very large databases, in most cases with a good I/O subsystem, and backup tuning (using multiple files, increasing transfer size) you can backup very large databases in a normal window. I manage a system that backs up 20 TB every day with Ola Hallengren’s scripts, and not even storage magic. Not all of these storage based solutions are bad, but as your move to larger vendors who are further and further removed from what SQL Server or Oracle are, you will likely run into problems. So ask a lot of questions, and ask for plenty of testing time.
So if you don’t like the answers you get, or the results of your testing, what do you do? The place to make the arguments are to the business team for the applications you support. Don’t do this without merit to your argument—you don’t want to unnecessarily burn a bridge with the infrastructure folks, but at the end of the day your backups, and more importantly your recovery IS YOUR JOB AS A DBA, and you need a way to get the best outcome for your business. So make the argument to your business unit, that “Insert 3rd Party Snapshot Magic” here isn’t a good data protection solution and have them raise to the infrastructure management.
Something that has come from Microsoft in the last couple of months is the ability to provision an Azure Virtual Machine (VM) with fewer CPUs, than the machine has allocated to it. For example, by default a GS5 VM has 32 CPUs and 448 GB of memory. Let’s say you want to migrate your on-premises SQL Server that has 16 cores and 400 GB of RAM. Well, if you wanted to use a normal GS5, you would have to license an additional 16 cores of SQL Server (since you have all that RAM I’m assuming that you are using Enterprise Edition). Now, with this option, you can get a GS5 with only 16 (or 8) CPUs.
I can hear open source database professionals laughing at turning down CPUs, but this is a reality in many Oracle and SQL Server organizations, so Microsoft is doing us a favor. This doesn’t apply to all VM classes, and currently the pricing calculator does not show these options, however they are in the Azure portal when you select a new VM for creation. The costs of these VMs are the same as the fully allocated ones, though if you are renting your SQL Server licenses through Azure those costs are less.
This option is available on the D, E, G, and M series VMs, and mainly on the larger sizes in those series. If you would like to see cores reduced on other VM sizes, send feedback to Microsoft.
I did a postcon at Live360 in Orlando last week, and I promised that I would share the resources I talked about during the event. I’d like to thank everyone who attended, it was the end of a long conference, and the audience was attentive and had lots of great questions. So anyway here goes in terms of resources that we talked about during the session:
1) Automated build scripts for installing SQL Server.
2) SentryOne Plan Explorer
3) Glenn Berry’s Diagnostic Scripts- (B|T) These were the queries I was using to look at things like Page Life Expectancy, Disk Latency on the plan cache, Glenn’s scripts are fantastic and he does and excellent job of keeping them up to date.
4) SP_WhoIsActive this script is from Adam Machanic (b|t) and will show you what’s going on a server at any point in time. You have the option of logging this to a table or getting replication.
Finally, my slides are here. Thanks everyone for attending and thanks 1105 Media for a great conference.
Not to sound too much like Juan Antonio Samaranch, but 2017 was truly the best Speaker Idol I’ve ever had the pleasure of judging (and I’ve been judgy at all of them). I would foremost like to thank Tom LaRock (b|t) for stepping in as an emcee while Denny Cherry was ailing. Tom did an excellent job of keeping the contest flowing, and his stage presence and sense of humor kept our audience (and judges) entertained. I am also taking the opportunity of this post to document two new rules that we are introducing to Speaker Idol for 2018. (I think the official rules may be in a OneNote somewhere, or it’s just tribal knowledge between Denny and I):
- Contestants, or any representatives of contestants may have no written or internet communications related in any way to the judging of the contest with judges during the period of the competition. (Which is defined as the moment the first speaker idol contestant speaks, until the final decision of the winner is announced). Penalty is disqualification and removal from final.
This means if you won, you aren’t allowed to ask (or have anyone else ask) the judges what you did right/wrong in your talk. I would extend this rule only to round winners, but since runner ups have the ability to wildcard into the finals, or if a round winner does this they could automatically be promoted, the rule applies to everyone. You are free to ask judges for their feedback after the competition, but the for the most part, what we say to you on stage is our feedback. If it was really bad, we might be a little nice, but you likely know it was really bad. You can still say hi to a judge at the conference, but don’t ask them how you could improve.
2. No gifts of any value may be offered to judges within a 90 day period before and after the competition.
I chose 90 days somewhat arbitrarily for this, because I don’t think we name contestants 90 days before Summit. And if you care enough to buy judges 30 year old scotch 3 months after the competition, more power to you. If you want to give a judge a sticker, or a business card, outside the competition room, that is acceptable. Nothing more. Sticker or business card. No free training. Or logins to your site.
That’s enough about rules. Let’s talk about the competition.
The Level of Quality was High
As judges, we’ve never actually had to calculate scores before. For this years final round, we actually flipped over the sign in front of the room and objectively scored our top two on the following:
Everyone who made it to the final was good. Really good. Each of them would be a fine speaker at Summit. So what were the differences? When competitions are there close, scoring comes down to very minor factors like body movement on stage, ticks in delivery, and making the most of your time. Another factor is taking feedback from the earlier rounds and incorporating it into your presentation. Almost all of our contestants improved from their preliminary round—if you made it to the final, congratulations you did and excellent job.
Why the Winner Won
There’s a saying I’ve heard in sports, particularly amongst hitters in baseball, and quarterbacks in football, and I can tell you it also holds true in bike racing, that as you become more experienced, everything around you seems to slow down and lets you observe more of what’s going on in the moment, than someone who is less experienced. The same thing applies to public speaking—when you first do it, you feel nervous, and rushed, and you don’t feel like you can just relax and be yourself. The biggest difference between our winner, and our second place competitor, was that Jeremy was relaxed, delivered his content slowly, so that it could be easily consumed, and conveyed a complex technical concept in a manner that was easily understandable. Both presentations were excellent, Jeremy’s simply rose above.