Welcome!

Related Topics: @BigDataExpo, Java IoT, Microservices Expo, Linux Containers, Machine Learning , Agile Computing

@BigDataExpo: Article

Software Quality Metrics for Your Continuous Delivery Pipeline | Part 2

The metrics around database access

No matter how often you deploy your application or how sophisticated your delivery pipeline is, you always need to know the quality status of the software you are building. That can only be done if you measure it; but measure what exactly? In Part 1 we introduced the Concept of Quality Metrics in CD (Continuous Delivery) by looking at the metric # of Requests per End User Action. In Part 2 we will focus on metrics around database access.

You need to be aware of bad database access patterns right when they get introduced in your code. Whether the reason is incorrectly configured O/R (Object Relational) Mappers such as Hibernate, TopLink or JDO, or because of bad coding. Finding these problems immediately by looking at the right metrics will make it is easier for developers to fix the problem, which will reduce test cycles and give operations more confidence that a new deployment will not blow their current database server.

Examples of Bad Database Access Patterns
The following example is taken from a web application that displays an account report with 25 items per page that contains the names and high-level statuses of these accounts. The developers decided to go with Hibernate in order to access these account objects stored in the database. A closer look at the generated SQL queries when generating this report reveals that Hibernate not only loads the account objects that match the search query, but actually loads all account objects including all referenced objects in a related history table. These history objects are not needed at all to generate the report. The way Hibernate is used by the application (premature loading of all objects and referenced objects) results in more than 4000 SQL executions contributing 6s to the total page load time:

The way Hibernate is used by the application results in 4k+ individual SQL Statements, returning much more data than is actually needed for the report

If you want to learn more about database access problems check out load balancers cause database locks, when it is really the database to blame or the "Understanding Hibernate" Series: Part I - Session Cache, Part II - Query Cache and Part III - Second Level Cache.

Metric: Total Number of SQL Statements per Transaction
The first metric you want to take a closer look at is the total number of SQL executions per transaction. If you want to go a step further you can even monitor SELECT, INSERT, DELETE and UPDATE statements separately.

If you're always aware how many database statements are executed for your individual transactions (Login, Search, Checkout) and you monitor this along the delivery pipeline for every build, you will immediately see how the newly added functionality impacts the load on your database. The following screenshot shows a way to track this number across builds and across your different deployment stages. In this scenario, Developers extended the search feature in Build #3 by making an additional call to a 3rd party recommendation service. Build #3 suddenly shows a huge spike in SQL queries in the Load Stage and Production. Why is that?

A new call to an external third-party service introduced with Build 3 has major impacts on the load (capacity stage) and production environment when this new feature has to deal with real production data

What can we learn from these metrics above?

  • Commit stage: The executed Unit Tests in that stage didn't catch the problem because the call to the third-party service was mocked and therefore no actual DB calls were executed by that service.
  • Acceptance stage: A change in behavior was detected due to the additional call to the recommendation service which executed 2 additional SQLs. This could already be a warning sign but will probably still stay unnoticed.
  • Capacity stage: a 200x increase in DB calls must stop this deployment so that it never reaches Live. The reason why we have 200x and not only two should also trigger the integration tests to be executed against more than sample database content.
  • Production: 4k SQLs instead of just two is a huge impact on production. This again can be explained because the production database has "real life" data and the database access pattern of this third-party service queries every piece of data. If this really makes it into production and we monitor this data down to the transaction level, it is easy to pull this change back and engineering can immediately start working on the problematic area. Most important, however, is that this build never makes it into production because the problem was found in testing already!

How to Measure on Dev Workstations
Developers can look at this data by either turning on certain SQL Logging options of the frameworks that they are using, e.g., Hibernate (see stackoverflow discussion). They can profile their code using the profiler that comes with their IDE or use tools such as the Development Edition of dynaTrace (or the 15 Days Free Trial) to see all database calls made by their own code or the code that they are calling. The following shows a screenshot taken from Database Access Patterns Gone Wild and shows which data can be analyzed on a local machine:

Developers can analyze which SQL statements are executed by their own code or third-party frameworks they use. In this case it was code executed by Telerik to populate .NET control data.

For more measurement tips, and for further insight, click here for the full article

More Stories By Andreas Grabner

Andreas Grabner has been helping companies improve their application performance for 15+ years. He is a regular contributor within Web Performance and DevOps communities and a prolific speaker at user groups and conferences around the world. Reach him at @grabnerandi

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Latest Stories
@ThingsExpo has been named the Top 5 Most Influential Internet of Things Brand by Onalytica in the ‘The Internet of Things Landscape 2015: Top 100 Individuals and Brands.' Onalytica analyzed Twitter conversations around the #IoT debate to uncover the most influential brands and individuals driving the conversation. Onalytica captured data from 56,224 users. The PageRank based methodology they use to extract influencers on a particular topic (tweets mentioning #InternetofThings or #IoT in this ca...
Have you ever noticed how some IT people seem to lead successful, rewarding, and satisfying lives and careers, while others struggle? IT author and speaker Don Crawley uncovered the five principles that successful IT people use to build satisfying lives and careers and he shares them in this fast-paced, thought-provoking webinar. You'll learn the importance of striking a balance with technical skills and people skills, challenge your pre-existing ideas about IT customer service, and gain new in...
In recent years, containers have taken the world by storm. Companies of all sizes and industries have realized the massive benefits of containers, such as unprecedented mobility, higher hardware utilization, and increased flexibility and agility; however, many containers today are non-persistent. Containers without persistence miss out on many benefits, and in many cases simply pass the responsibility of persistence onto other infrastructure, adding additional complexity.
Tintri VM-aware storage is the simplest for virtualized applications and cloud. Organizations including GE, Toyota, United Healthcare, NASA and 6 of the Fortune 15 have said "No to LUNs." With Tintri they manage only virtual machines, in a fraction of the footprint and at far lower cost than conventional storage. Tintri offers the choice of all-flash or hybrid-flash platform, converged or stand-alone structure and any hypervisor. Rather than obsess with storage, leaders focus on the business app...
@DevOpsSummit at Cloud taking place June 6-8, 2017, at Javits Center, New York City, is co-located with the 20th International Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time to wait for long developm...
WebRTC has had a real tough three or four years, and so have those working with it. Only a few short years ago, the development world were excited about WebRTC and proclaiming how awesome it was. You might have played with the technology a couple of years ago, only to find the extra infrastructure requirements were painful to implement and poorly documented. This probably left a bitter taste in your mouth, especially when things went wrong.
In his general session at 18th Cloud Expo, Lee Atchison, Principal Cloud Architect and Advocate at New Relic, discussed cloud as a ‘better data center’ and how it adds new capacity (faster) and improves application availability (redundancy). The cloud is a ‘Dynamic Tool for Dynamic Apps’ and resource allocation is an integral part of your application architecture, so use only the resources you need and allocate /de-allocate resources on the fly.
More and more brands have jumped on the IoT bandwagon. We have an excess of wearables – activity trackers, smartwatches, smart glasses and sneakers, and more that track seemingly endless datapoints. However, most consumers have no idea what “IoT” means. Creating more wearables that track data shouldn't be the aim of brands; delivering meaningful, tangible relevance to their users should be. We're in a period in which the IoT pendulum is still swinging. Initially, it swung toward "smart for smart...
SYS-CON Events announced today that Technologic Systems Inc., an embedded systems solutions company, will exhibit at SYS-CON's @ThingsExpo, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Technologic Systems is an embedded systems company with headquarters in Fountain Hills, Arizona. They have been in business for 32 years, helping more than 8,000 OEM customers and building over a hundred COTS products that have never been discontinued. Technologic Systems’ pr...
Cloud Expo, Inc. has announced today that Andi Mann and Aruna Ravichandran have been named Co-Chairs of @DevOpsSummit at Cloud Expo 2017. The @DevOpsSummit at Cloud Expo New York will take place on June 6-8, 2017, at the Javits Center in New York City, New York, and @DevOpsSummit at Cloud Expo Silicon Valley will take place Oct. 31-Nov. 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
DevOps is often described as a combination of technology and culture. Without both, DevOps isn't complete. However, applying the culture to outdated technology is a recipe for disaster; as response times grow and connections between teams are delayed by technology, the culture will die. A Nutanix Enterprise Cloud has many benefits that provide the needed base for a true DevOps paradigm.
Why do your mobile transformations need to happen today? Mobile is the strategy that enterprise transformation centers on to drive customer engagement. In his general session at @ThingsExpo, Roger Woods, Director, Mobile Product & Strategy – Adobe Marketing Cloud, covered key IoT and mobile trends that are forcing mobile transformation, key components of a solid mobile strategy and explored how brands are effectively driving mobile change throughout the enterprise.
In his session at @ThingsExpo, Steve Wilkes, CTO and founder of Striim, will delve into four enterprise-scale, business-critical case studies where streaming analytics serves as the key to enabling real-time data integration and right-time insights in hybrid cloud, IoT, and fog computing environments. As part of this discussion, he will also present a demo based on its partnership with Fujitsu, highlighting their technologies in a healthcare IoT use-case. The demo showcases the tracking of patie...
SYS-CON Events announced today that Outlyer, a monitoring service for DevOps and operations teams, has been named “Bronze Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Outlyer is a monitoring service for DevOps and Operations teams running Cloud, SaaS, Microservices and IoT deployments. Designed for today's dynamic environments that need beyond cloud-scale monitoring, we make monitoring effortless so you...
In his session at 20th Cloud Expo, Chris Carter, CEO of Approyo, will discuss the basic set up and solution for an SAP solution in the cloud and what it means to the viability of your company. Chris Carter is CEO of Approyo. He works with business around the globe, to assist them in their journey to the usage of Big Data in the forms of Hadoop (Cloudera and Hortonwork's) and SAP HANA. At Approyo, we support firms who are looking for knowledge to grow through current business process, where even ...