Voice of the DBA

Tag: Database Weekly

  • Achieve Better Performance

    One of the hottest topics at most every SQL Server event I attend is performance. The sessions that talk about improving performance through various means are well attended, and that tells me a few things. One is this is an important topic, and two, people need to learn more about it.

    This past week I noticed a lot of performance related topics appearing in blogs and headlines. I’m not sure why there were so many this week, but I think it does deserve pointing out that this is a good week to beef up your skills in this area. I saw a little bit of something for everyone, no matter what your job.

    Database administrators, who often deal with the end product from developers and can make limited changes, should make sure they understand statistics, which can clue them into problems in a number of situations. You ought to be able to troubleshoot various issues, like blocking or tempdb issues. For those dealing with merge replication issues, you ought to ensure you understand how to deal with conflicts and resolve them. No matter who you are, you need to understand the impact of IO on your server, and that means ensuring you can measure the load. Measuring CPU can be tricky, but there’s an interesting idea from the SQL Server team this week.

    The developers, who can make changes early in the process of software development, really should learn to write better SQL. That means studying the various ways people solve problems and practicing using some of them. Do you know the issues with Scalar UDFs? Do you understand temporary objects? Can you PIVOT data? There are so many writings on T-SQL that you can’t keep up, but you should be getting better over time if you write T-SQL code in your job.Developers also should understand the basics of indexing, and deliver a few basic indexes along with their software. That’s the least you can do.

    This week we started to see various blogs on SQL Server 2014, especially the Hekaton feature. While I’m sure the next version of SQL Server will perform better and speed up some of your workloads, it can’t cover from fundamental mistakes, at least not completely. Do your career, and your current and future employers a favor and work on your performance skills this week.

  • State of the Cloud

    The Azure cloud is doing well.
    The Azure cloud is doing well.

    Microsoft has joined the billion dollar club. For Azure, that is. They announced that this platform and service will generate a billion dollars in revenue. It’s been growing, and at least one analyst expects the revenue to double annually. Profit is something else, but I know from various people at Microsoft that they are working hard and investing heavily in this service, and I’m sure at some point it will be profitable, though I’m not sure how much.

    Amazon has had a very successful AWS platform, providing a wide variety of services and products. Their aim is to go for the high volume, low margin business, which makes their service competitive with the costs of buying and managing your own hardware. As long as Amazon and other competitors are out there, I suspect cloud services will be cheap enough to make many companies consider moving some of their infrastructure to this type of environment. It certainly eases the time and effort of building new machines and encourages better development habits.

    As IT departments, especially the management of those groups consider using cloud type services, they still have to be aware that this isn’t a savings that comes for free. Code changes, staffing skill growth and mindset evolutions to take into the account the challenges of working in a cloud environment, as well as the SLAs that seem to favor the cloud providers more than the cloud customers, mean this isn’t an easy decision. Add to this the potential tax implications, and the decision to move away from current IT practices is not always obvious.

    The idea of cloud computing, and cloud services, is still very immature. From the definition of what this means, to the offerings, to the architectures, the industry has a lot of growth to do before most of us will feel comfortable moving substantial parts of our infrastructure out of our own facilities.

  • The Memory Cube

    How would you like memory in your SQL Server that’s 15 times as fast as your current DDR3 DRAM? I know I would, and since memory is often one of the things that can dramatically speed up, or hinder, SQL Server performance, this article about new memory cubes is good news. Over 100 companies have signed on to the specifications for three dimensional DRAM, which stacks memory dies on top of each other.
    How much better is the performance? Try 160GBps for this cube against the 11GBps that we typically see from DDR3. Even DDR4 is only 18-20GBps of aggregate bandwidth. What’s more, this new technology should require less power. That’s a good sign as more and more data centers are finding that power and cooling are significant issues and can end up being a significant percentage of the total cost of operating computer systems.
    This technology isn’t quite ready for production, as the prototypes only hold 2GB and 4GB of memory right now. However I would expect that to grow quickly as memory companies look to get production cubes out in 2013. The deployment will likely start in network devices and other environments where extremely high speed memory is needed, but I could see that server computers, especially those slated to handle large numbers of virtual machines, will move to this technology once capacities get over 32GB. At that point, there could be lots of OLTP systems that would benefit from faster access to memory, especially those systems backing high volume, (relatively) low storage systems.
    The bottleneck for many systems will continue to be the disk drives, but if you can process more data in memory, at a much faster rate, I’m sure there are lots of DBAs that would love to use this technology to reduce the number of complaints from their clients.
    Steve Jones

  • SSD Lifetimes

    Samsung 840 SSD
    This looks like a nice SSD upgrade that’s reliable.

    One of the things that has concerned many DBAs looking at SSD drives is the possible limited life of these drives. In the past, many consumer drives have had issues, and can fail without warning. However there are plenty of people that still love them for the fact that they are crazy fast and can dramatically speed up your system. Just make sure you keep good backups of your data since it may not be recoverable.

    For servers, a number of manufacturers have been working hard to build more reliability and longer lifetimes into their drives. FusionIO has listed 2 million hours and 6 years write endurance for their cards, which is a quite a long time. Other manufacturers are working hard as well and I suspect we’ll see more and more SSDs architected into SQL Server instances over the next few years. Microsoft has a white paper on using FusionIO cards in tempdb, and I know a few SQL Server installations have been quite pleased with their results of using these cards in production systems.

    This week I saw an analysis of the Samsung SSD 840 over at AnandTech. They examined the wear of this drive and came to the conclusions that writing over 10GiB a day, you’re still get many years of service from this drive. That gives me a lot of confidence in the drive, and with Amazon listing the 250GB version for $180, it’s an upgrade you might consider for your laptop.