With the rise of technologies like smartphones, retailers have felt the pressure to meet evolving consumer needs and expectations. Seven-Eleven Japan(“SEJ”) has long been on the forefront of this thanks to the way they develop and invest in IT. However, in recent years, Japan’s leading convenience store chain has struggled to maintain its complex legacy systems at the rate needed to keep up with today’s rapid digitization, spurred on by the increasing proliferation of smartphones and an IT vendor-dependent structure.  

Legacy systems limiting real-time responsiveness and innovation 

Since its early days, SEJ has been proactive in adopting information technology, mainly relying on technology solutions from Japan’s leading vendors. But as the systems have grown, key business issues have been resolved using a vendor-dependent structure rather than being driven by SEJ’s own needs.  

Datasets and business logic were combined and built into legacy environments, gradually leading to data silos. As a result, data was distributed across multiple systems, causing a variety of problems, including the inability to efficiently retrieve data when needed, delays in accessing data collected in individual stores, and difficulties taking measurements at the right time in business operations that require real-time responsiveness.

Connecting different systems also takes time and money, and the lead time for introducing new services—from planning to development and launch—has been longer than expected. 

To solve these problems, SEJ’s IT department built “Seven Central”—a new platform for practical data use launched in 2020 to support the company’s future IT strategies and digital transformation initiatives.

At its core, Seven Central’s ultimate purpose is to allow real-time data views. Versatile, real-time datasets—such as point-of-sale (POS) data from 7-Eleven stores—are consolidated into a centralized location in the cloud. They created a simple data mart that provides data via an API to enable them to respond more quickly to requests from individual departments. 

“In such uncertain times, it’s vital to use data to make quick decisions,” says Izuru Nishimura, Executive Officer and Head of ICT Department. “Each department across the entire company will be able to gain an immediate understanding of the situation based on the most up-to-date data and respond accordingly. This is why we built Seven Central.”

Google Cloud selected to help SEJ build and grow their data cloud

Today’s rapidly changing business environment has also highlighted the risk of IT support becoming a bottleneck. The long-term strategy is to gradually expand the datasets managed and collected in Seven Central according to business needs. 

In the first phase, SEJ collected POS data from all 21,000+ stores to enable real-time analysis. Moving forward, they would like to collect other relevant data—for example, unstructured data, such as images and videos, or master datasets that are currently stored externally. 

Google Cloud was already a top contender when SEJ started developing Seven Central in 2019. They compared various public cloud services besides Google Cloud, focusing on three main capabilities.

“We placed particular emphasis on service scalability to drive future digital transformation; security when handling data, which is the lifeline of our company; and finally, openness,” says Nishimura. He emphasizes that openness was perhaps the most important factor for choosing Google Cloud. Breaking away from the negative aspects of an entirely vendor-dependent system enabled them to build an agile development system with multiple vendors. 

Google Cloud technologies including BigQuery and API management platform, Apigee, play a vital role in Seven Central. BigQuery’s high-speed processing at petabyte scale and fully managed infrastructure helped keep costs low during development and verification.   

“Data is stored in a way that allows you to share it easily across organizations, which helps solve the issue of data silos from the perspective of scalability. I also like the fact there are some interesting features that could be used in the future—like BigQuery ML, which enables machine learning on BigQuery,” says Nishimura. 

Apigee allows SEJ to separate datasets and business logic, which is one of the key points of Seven Central. While the trend these days is to standardize interfaces using an API, the reality tends to involve many different APIs rather than the introduction of one unified API. With Apigee, SEJ provides a single unified API for all of its data cloud, and they can now understand what data is used thanks to Apigee’s API usage visualizations.  

“Right now, we collect data from all 21,000+ stores,” says Nishimura. “But in anticipation of a future expansion in business operations, we have designed a system that can scale up and run without issue, even if we were to have 30,000 stores, with 1,000 customers per store per day, purchasing five items per person.”

Real-time insights with BigQuery and Cloud Spanner

Google Cloud partner Cloud Ace came on board early in the planning phases. Based on their recommendations, SEJ decided to continue making full use of BigQuery to analyze data collected from all 21,000+ stores throughout Japan, while also using Cloud Spanner’s availability, near-unlimited scalability and transactional consistency to help achieve the real-time results needed for the project.

“Given that both the data and the regularity with which it is accessed are expected to steadily increase in the future, we chose Cloud Spanner as backend storage for data delivery via API. We consider it a good choice,” says Shota Kikuchi, General Manager, Consulting Department, Technology Division, Cloud Ace Co., Ltd.

Finally, they chose to use Google Cloud’s Stream Analytics Solutions messaging service for collecting POS data in real time, which can then be put to immediate use with Cloud Spanner and BigQuery. 

High-speed responses exceed targets and create new value 

Seven Central went live in September 2020 with surprising results. 

They initially set a target time of one hour from when a customer makes a purchase to the point when Seven Central can use that data. But when the final system was first tried—it took barely a minute. Moving forward they estimate that the latest inventory data from the service side will become available within a few minutes of being added to the system.  

“This is real innovation, and I must admit that I am quite surprised. As well as being able to solve existing issues, we also hope it will lead to new improvements and services that have been unimaginable up until now,” says Nishimura.

The team hopes to roll out the Seven Central platform in all companies affiliated with Seven & i Holdings—not just SEJ. They also plan to explore Google Cloud AI and machine learning technologies to take on challenges in new areas. For example, they are investigating the idea of clustering individual stores using BigQuery ML.

Seven Central has already attracted attention from many departments and received a lot of requests. Nishimura and his team say they hope to continue to grow Seven Central while still observing their fundamental principles—not including business logic, maintaining real-time results, and staying true to the uniqueness of SEJ.

Learn more about Google Cloud smart analytics solutions.

When customers migrate to Google Cloud Platform (GCP), their first step is often to adopt Compute Engine, which makes it easy to procure and set up virtual machines (VMs) in the cloud that provide large amounts of computing power. Launched in 2012, Compute Engine offers multiple machine types, many innovative features, and is available in 20 regions and 61 zones! 

Compute Engine’s predefined and custom machine types make it easy to choose VMs closest to your on-premises infrastructure, accelerating the workload migration process cost effectively. Cloud allows you the pricing advantage of ‘pay as you go’ and also provides significant savings as you use more compute with Sustained Use Discounts. 

As Technical Account Managers, we work with large enterprise customers to analyze their monthly spend and recommend optimization opportunities. In this blog, we will share the top recommendations that we’ve developed based on our collective experience working with GCP customers. 

Getting ready to save

Before you get started, be sure to familiarize yourself with the VM instance pricing page—required reading for anyone who needs to understand the Compute Engine billing model and resource-based pricing. In addition to those topics, you’ll also find information about the various Compute Engine machine types, committed use discounts and how to view your usage, among other things. 

Another important step to gain visibility into your Compute Engine cost is using Billing reports in the Google Cloud Console and customizing your views based on filtering and grouping by projects, labels and more. From there you can export Compute Engine usage details to BigQuery for more granular analysis. This allows you to query the datastore to understand your project’s vCPU usage trends and how many vCPUs can be reclaimed. If you have defined thresholds for the number of cores per project, usage trends can help you spot anomalies and take proactive actions. These actions could be rightsizing the VMs or reclaiming idle VMs.

Now, with these things under your belt, let’s go over the five ways you can optimize your Compute Engine resources that we believe will give you the most immediate benefit. 

1. Apply Compute Engine rightsizing recommendations

Compute Engine’s rightsizing recommendations feature provides machine type recommendations that are generated automatically based on system metrics gathered by Stackdriver Monitoring over the past eight days. Use these recommendations to resize your instance’s machine type to more efficiently use the instance’s resources. It also recommends custom machine types when appropropriate. Compute Engine makes viewing, resizing and other actions easier right from the Cloud Console as shown below. 

Recently, we expanded Compute Engine rightsizing capabilities from just individual instances to managed instance groups as well. Check out the documentation for more details.

For more precise recommendations, you can install the Stackdriver Monitoring agent which collects additional disk, CPU, network, and process metrics from your VM instances to better estimate your resource requirements. You can also leverage the Recommender API for managing recommendations at scale.

2. Purchase Commitments

Our customers have diverse workloads running on Google Cloud with differing availability requirements. Many customers follow a 70/30 rule when it comes to managing their VM fleet—they have constant year-round usage of ~70%, and a seasonal burst of ~30% during holidays or special events. 

If this sounds like you, you are probably provisioning resources for peak capacity. However, after migrating to Google Cloud, you can baseline your usage and take advantage of deeper discounts for Compute workloads. Committed Use Discounts are ideal if you have a predictable steady-state workload as you can purchase a one or three year commitment in exchange for a substantial discount on your VM usage.

We recently released a Committed Use Discount analysis report in the Cloud Console that helps you understand and analyze the effectiveness of the commitments you’ve purchased. In addition to this, large enterprise customers can work with their Technical Account Managers who can help manage their commitment purchases and work proactively with them to increase Committed Use Discount coverage and utilization to maximize their savings.

3. Automate cost optimizations

The best way to make sure that your team is always following cost-optimization best practices is to automate them, reducing manual intervention.

Automation is greatly simplified using a label—a key-value pair applied to various Google Cloud services. For example, you could label instances that only developers use during business hours with “env: development.” You could then use Cloud Scheduler to schedule a serverless Cloud Function to shut them down over the weekend or after business hours and then restart them when needed. Here is an architecture diagram and code samples that you can use to do this yourself. 

Using Cloud Functions to automate the cleanup of other Compute Engine resources can also save you a lot of time and money. For example, customers often forget about unattached (orphaned) persistent disk, or unused IP addresses. These accrue costs, even if they are not attached to a virtual machine instance. VMs with the “deletion rule” option set to “keep disk” retain persistent disks even after the VM is deleted. That’s great if you need to save the data on that disk for a later time, but those orphaned persistent disks can add up quickly and are often forgotten! There is a Google Cloud Solutions article that describes the architecture and sample code for using Cloud Functions, Cloud Scheduler, and Stackdriver to automatically look for these orphaned disks, take a snapshot of them, and remove them. This solution can be used as a blueprint for other cost automations such as cleaning up unused IP addresses, or stopping idle VMs. 

4. Use preemptible VMs

If you have workloads that are fault tolerant, like HPC, big data, media transcoding, CI/CD pipelines or stateless web applications, using preemptible VMs to batch-process them can provide massive cost savings. In fact, customer Descartes Labs reduced their analysis costs by more than 70% by using preemptible VMs to process satellite imagery and help businesses and governments predict global food supplies.

Preemptible VMs are short lived— they can only run a maximum of 24 hours, and they may be shut down before the 24 hour mark as well. A 30-second preemption notice is sent to the instance when a VM needs to be reclaimed, and you can use a shutdown script to clean up in that 30-second period. Be sure to fully review the full list of stipulations when considering preemptible VMs for your workload. All machine types are available as preemptible VMs, and you can launch one simply by adding “-preemptible” to the gcloud command line or selecting the option from the Cloud Console. 

Using preemptible VMs in your architecture is a great way to scale compute at a discounted rate, but you need to be sure that the workload can handle the potential interruptions if the VM needs to be reclaimed. One way to handle this is to ensure your application is checkpointing as it processes data, i.e., that it’s writing to storage outside the VM itself, like Google Cloud Storage or a database. As an example, we have sample code for using a shutdown script to write a checkpoint file into a Cloud Storage bucket. For web applications behind a load balancer, consider using the 30-second preemption notice to drain connections to that VM so the traffic can be shifted to another VM. Some customers also choose to automate the shutdown of preemptible VMs on a rolling basis before the 24-hour period is over, to avoid having multiple VMs shut down at the same time if they were launched together. 

5. Try autoscaling 

Another great way to save on costs is to run only as much capacity as you need, when you need it. As we mentioned earlier, typically around 70% of capacity is needed for steady-state usage, but when you need extra capacity, it’s critical to have it available. In an on-prem environment, you need to purchase that extra capacity ahead of time. In the cloud, you can leverage autoscaling to automatically flex to increased capacity only when you need it. 

Compute Engine managed instance groups are what give you this autoscaling capability in Google Cloud. You can scale up gracefully to handle an increase in traffic, and then automatically scale down again when the need for instances is lowered (downscaling). You can scale based on CPU utilization, HTTP load balancing capacity, or Stackdriver Monitoring metrics. This gives you the flexibility to scale based on what matters most to your application. 

High costs do not compute

As we’ve shown above, there are many ways to optimize your Compute Engine costs. Monitoring your environment and understanding your usage patterns is key to understanding the best options to start with, taking the time to model your baseline costs up front. Then, there are a wide variety of strategies to implement depending on your workload and current operating model. 

For more on cost management, check out our cost management video playlist. And for more tips and tricks on saving money on other GCP services, check out our blog posts on Cloud Storage, Networking and BigQuery cost optimization strategies. We have additional blog posts coming soon, so stay tuned!

Editor’s note: Bitly, the link & QR Code management platform, migrated 80 billion rows of link data to Cloud Bigtable. Here’s how and why they moved this data from a MySQL database, all in just six days.

Our goal at Bitly is simple: Make your life easier with connections. Whether you’re sharing links online, connecting the physical and digital worlds with custom QR Codes or creating a killer Link-in-bio, we’re here to help make that happen.

Bitly customers run the gamut from your local middle school to most of the Fortune 500 with every use case you can think of in play. On a typical day, we process approximately 360 million link clicks and QR Code scans and support the creation of 6-7 million links or QR Codes for more than 350,000 unique users.

At the heart of our platform is link data consisting of three major datasets for the approximately 40 billion active links in our system (and counting). For years we stored this data in a self-managed, manually sharded MySQL database. While that setup served us well over time, it did present some challenges as we looked to expand and move into the future. 

MySQL: Challenges and growing pains

First, performing operational actions like software and security upgrades or database host provisioning — all while keeping the databases 100% available for our customers — was challenging to say the least.

Additionally, the backup and restore process was both costly and time-consuming. Daily backups for the growing dataset took almost an entire day to complete. And if we ever had to restore the entire data set, it would have undoubtedly taken at least two people working for several days — not a fun prospect and thankfully something we never had to do.

While manual sharding for MySQL offers good key distribution across physical and logical shards, it’s pretty high-maintenance — we tried to avoid touching our sharding config because of how error-prone making changes was. And even with a forward-thinking shard allocation, we found this approach to have a limited lifespan. 

And finally, when we turned our attention towards multi-region and global distribution, manually sharded MySQL proved to be a major hurdle, especially compared to the convenience of a managed service that handles geo-distribution for us.

As we thought about the future of our data and how to best meet our expansion goals, we determined that an update was necessary. We needed a system more set up for growth and increased reliability, preferably one with built-in functionality for replication and scaling. Investigation and research brought us to Cloud Bigtable, Google Cloud’s enterprise-grade NoSQL database service.

The Bitly link, in a nutshell

Before we dive into the Bigtable migration, it’s useful to understand the basics of our link management system. When a user shortens a long URL with Bitly, information is saved to the backend data stores through our API layer. This information consists of a Bitly short link and the corresponding destination link for proper routing, as well as some additional metadata. When a user clicks the Bitly short link, our services query these same backend data stores for the redirect destination for the request. This basic flow, which also includes other Bitly link options like custom back-halves, is the backbone of the Bitly link management platform.

Where Bigtable comes in

As mentioned, after researching our options, the solution that best fit our needs was Bigtable. It offered the features we were looking for, including:

• A 99.999% SLA 
• Limitless scale
• Single-digit millisecond latency
• A built-in monitoring system 
• Multi-region replication
• Geo-distribution, which allows for seamless replication of data across regions and reduces latency
• On-demand scaling of compute resources and storage, which adjusts to user traffic and allows our system to grow and scale as needed
• Seamless integration with our general architecture; we use Google Cloud services for many other parts of our system, including the APIs that interact with these databases
• A NoSQL database that doesn’t require relational semantics, as the datasets we’re migrating are indexed on a single primary key in our applications 

Making the move

We targeted three of our major, self-managed datasets to migrate. The larger two were organized in a sharded database architecture. The first thing we did for migration was prepare the new Bigtable database. We iterated over a schema design process and conducted a thorough performance analysis of Bigtable to ensure an uninterrupted user experience during and after the migration. After that, we made minor adjustments to our application code so that it could seamlessly integrate and interact with Bigtable. Finally, we implemented a robust post-migration disaster recovery process to mitigate any potential risks.

During the actual migration, we enabled our applications to start a “dual writes” phase. This involved concurrently writing new link data to both our existing MySQL and the new Bigtable tables. Once data started writing to our Bigtable instance, we ran our migration scripts. We used a Go script to walk each of the existing MySQL datasets and insert each row into Bigtable. This enabled us to clean up outdated information and backfill older records with newer field data. 

Cleaning up clutter along the way

In the process of migration, we were actually able to free up a huge amount of storage. Because of the elimination of an early feature of the Bitly platform, we were able to exclude from the migration to Bigtable a little less than half of the total data stored in MySQL. Since we were creating a completely clean dataset, we had the opportunity simply to skip those unneeded rows during the migration. 

Altogether, the migration process walked through 80 billion MySQL rows, which resulted in just over 40 billion records finding their new home in Bigtable. In the end, our starting point with Bigtable is a 26 TB dataset, not including replication. A set of concurrent Go scripts running in parallel on a handful of machines allowed us to complete this migration project in six days. (Go rarely disappoints.)

Write twice, cut once – validation before migration

Next up was the data validation and cutover period when we started returning data from Bigtable, but continued to write to MySQL as a precaution in case we needed to roll back at any point.

As we dove into the validation process, we compared the data between MySQL and Bigtable and noted any discrepancies whenever a link was clicked or created. After verifying that all our responses were stable, we proceeded with a gradual cutover process, rolling out in percentages until we reached 100% Bigtable for all writes and reads. After a comfortable run period, we’ll turn off the dual writes completely and finally decommission our workhorse MySQL hosts to live on a farm upstate.

Google’s got Bitly’s back(ups)

Our data is our lifeline, and we’re doing everything we can to ensure it’s always protected. We put together a redundancy plan using both Bigtable backups as well as a process for keeping a copy of the data outside Bigtable for true disaster recovery. 

The first line of defense involves a switchover to the backup Bigtable dataset in case we need it. Beyond that, we’ve implemented two more layers of defense to protect against instance failure, corrupted data, and any other data failure that would require a restore of one or more tables from backup. 

For this process, we start by creating daily Bigtable backups of our tables that we store for a fixed number of days. Second, we execute a Dataflow job to export our data from Bigtable into Cloud Storage approximately every week. And, if the need arises, we can use Dataflow to import our data back from Cloud Storage into a new Bigtable table.  

While running the Dataflow jobs to export from Bigtable to Cloud Storage, we’ve seen an impressive export speed of 7-8 million rows read per second on average and up to 15 million per second at times. All the while, our production reads and writes continued without disruption. When we tested the Cloud-Storage-to-Bigtable restore job, the write speed, expectedly, increased with instance scale — at the maximum node quota for our regions, we observed an average of just under 2 million rows per second written to our new table.

Short links for the long haul

As mentioned above, not only did Bigtable meet our technical requirements and operational needs, but we also chose Bigtable because it sets us up for future growth. Its ability to scale seamlessly over time while improving our system availability SLA was a major factor in our decision.

As we increase our scale by 5x, 10x, or more, it’s imperative that our data backbone scales accordingly and that the SLAs we provide to customers stay stable or even add another coveted “9”. We have big plans in the coming years and Bigtable will help us achieve them. 

Interested in learning more? We found the following resources to be useful in our journey to Bigtable evaluation and ultimate adoption:

• Evaluate Bigtable schema design for your relational database and application workloads
• Understand how to increase availability and distribute data globally with Bigtable replication in any region combination of your choice
• Learn more about Bigtable backups and importing/exporting data with Bigtable Dataflow templates

Bonus: If you’re interested in learning more of the nuts and bolts of how we migrated the data, I’ll be talking all about that very topic at GopherCon 2023 this September in San Diego!

The music industry is rapidly changing. Only 20 years ago, the availability of music and the infrastructure that was required to make an album a sales success were incredibly complex and expensive. With the decline of physical sales and a fundamental shift to digital, music streaming now accounts for more than half of all sales globally.

At the same time, technology has democratized music-making; in many ways, it has made the musical landscape more diverse. Artists can upload their music with the click of a button. But while it’s easier for creators to share their songs with audiences, getting paid has become more fragmented.

Although music is booming, people no longer buy it outright. Instead, listeners download music digitally or subscribe to streaming services to have their libraries with them at all times. To monetize digital content effectively, artists need to know when, where, and how often their songs are played on each service. To help them navigate this complicated royalties landscape and maximize their profits, Berlin-based international music company BMG provides customized, transparent, and fair services to songwriters and artists.

With publishing and recording divisions under one roof, the subsidiary of international media giant Bertelsmann works with both emerging artists and established stars, including John Legend, Kylie Minogue, Mick Jagger, and Keith Richards. With the MyBMG web and mobile application, clients can view and analyze their royalty details in real time and collect payment. When a new record is released, BMG uses data to maximize its impact and revenue for its creators.

“We make sure that everyone who uses our clients’ music knows who needs to be paid the associated royalties, then we collect these royalties and share them out quickly and transparently,” explains Sebastian Hentzschel, Chief Information Officer at BMG. “When our artists release new music, we make sure that it’s marketed and promoted effectively around the world.”

“We needed a scalable solution for our royalty workloads that was intuitive for our developers. We also wanted a partner, not a client-vendor relationship. With autoscaling via BigQuery, excellent customer support, and a clean and simple user interface, Google Cloud ticks every box for us.”

—Gaurav Mittal, Vice President Group Technology, BMG

Getting up to speed with a new way of paying artists

In this digital world, artists aren’t just paid every time a fan buys an album—they’re paid a small amount, or royalty, for each song downloaded or streamed by a listener. So, when the industry shifted to digital, the volume of data that BMG needed to handle grew exponentially. “One CD sale is equivalent to about 1,500 streamed songs or plays,” says Gaurav Mittal, Vice President Group Technology at BMG. “That means IT departments have to process 1,500 times the amount of data to calculate payments for artists, and this makes scalable micropayment processing very important.”

Until 2019, BMG’s infrastructure was entirely hosted on-premises. Hardware limitations made it challenging to scale on-demand, making it harder to handle the data peaks that royalty processing can bring. “With our on-premises infrastructure, we were going to hit a ceiling in a few years,” says Gaurav. “We still managed to process royalty payments for our clients, but it was increasingly time consuming and expensive. To keep focusing on our clients, rather than our infrastructure, we decided to migrate to Google Cloud.”

From the outset, Gaurav and his team had a clear vision for the partnership: “Most importantly, we needed a scalable solution for our royalty workloads that was intuitive for our developers. We also wanted a partner, not a client-vendor relationship,” he says. “With autoscaling via BigQuery, excellent customer support, and a clean and simple user interface, Google Cloud ticks every box for us.”

Keeping artists happy with business-as-usual payouts during migration

To move applications to the cloud while keeping payment cycles on track for its artists, BMG teamed up with Google Cloud partner Rackspace Technology. “We selected Rackspace Technology because it combines strong technical muscle and a global footprint, with the customer service of a local boutique firm,“ shares Gaurav.

BMG’s own technology team put together the outline for the Google Cloud architecture, which they passed on to Rackspace Technology for optimizations and the ultimate stamp of approval. Whenever Gaurav and his developers needed support, Rackspace Technology was ready to go. “So far, we’ve migrated 17 applications successfully, and Rackspace Technology has been 100% spot-on with each suggestion,” says Gaurav. “I can’t recall a single flaw in a Rackspace Technology-approved architecture, and that really says something.”

When BMG began its migration in August 2019, the team developed an ambitious two-year plan. Only 14 months later, however, the project is more than 75% complete. Among the solutions that BMG is using today are Cloud Storage to securely store 130 TB of data, and Cloud SQL as its standard database technology. The web applications run on Compute Engine, App Engine, and Google Kubernetes Engine.

“After successfully moving a few applications, it was clear that with the strong teamwork of BMG and Rackspace Technology, together with the ease of use of Google Cloud, we could speed up the project without sacrificing quality,” says Gaurav. “We’re set to complete our migration six months before schedule, helping us to quickly move out of our hybrid environment.”

“Our income-tracking teams are very savvy on the data, and the simplicity of Google Cloud empowers them to self-serve analytics, rather than wait for IT. Our teams are much more productive.”

—Gaurav Mittal, Vice President Group Technology at BMG

Royalty reporting and processing with BigQuery and Dataproc

So far, all of BMG’s critical workloads are up and running on Google Cloud. Royalty calculations, for example, which require incredible processing power and the collection of many micropayments to ensure full and timely payout, run entirely on Dataproc with output stored on BigQuery for downstream integration and reporting.

Enabling more harmonious workflows through self-serve analytics

As the new beating heart of BMG’s royalty reporting, BigQuery changed the rhythm of collaboration company-wide. In the past, income tracking teams had to contact IT departments if they needed deeper data insights for their work. By integrating Data Catalog with BigQuery, BMG has made the data more accessible to all teams. This helps them detect missing income and new revenue streams independently, maximizing profits for artists.

“Our income-tracking teams are very savvy on the data, and the simplicity of Google Cloud empowers them to self-serve analytics, rather than wait for IT,” says Gaurav. “Our teams are much more productive.”

“Google Cloud enables us to be more client focused and deliver better features faster. We believe it’s just the beginning. We offer rights and royalty services for music publishing, recorded music, neighboring rights, and books. Without scalability limitations, it’s absolutely conceivable to offer our platform as a service to other companies or industries, such as gaming. Google Cloud has opened a world of possibilities.”

—Sebastian Hentzschel, Chief Information Officer, BMG

With a leaner IT environment, BMG can focus its effort on the needs of its clients. Beyond improvements in royalty processing, it can concentrate on app development, releasing new features and enhancements more frequently. By hosting applications on Google Kubernetes Engine, App Engine, and Compute Engine, BMG has built a CI/CD pipeline with automated deployments and testing to significantly speed up workflows.

“In our old system, it could take several weeks to set up an environment,” says Gaurav. “With Google Kubernetes Engine, any of our developers can complete the process in a few clicks. Having that autonomy makes our developers more motivated and self-driven.”

“Google Cloud enables us to be more client focused and deliver better features faster,” adds Sebastian. “We believe it’s just the beginning. We offer rights and royalty services for music publishing, recorded music, neighboring rights, and books. Without scalability limitations, it’s absolutely conceivable to offer our platform as a service to other companies or industries, such as gaming. Google Cloud has opened a world of possibilities.”

With the migration almost complete, BMG is looking forward to its next technology project. It plans to leverage AutoML to further scale and automate royalty tracking with machine learning. On the marketing side, advanced analytics will help BMG determine the effectiveness of promotional campaigns around the world, further increasing profits for artists. By connecting Google Data Studio to BigQuery, BMG will increase the quality of its analyses, helping musicians better understand the reach of their music around the world.

In the end, Gaurav shares, helping musicians is what it all comes down to. “We’re a new kind of music company because we build our services around our artist, songwriter, and publisher clients, not the other way around,” he says. “Google Cloud is helping us maintain strong relationships with our clients, and that’s music to our ears.”

Bigtable is a scalable, distributed, high-performance NoSQL database that processes more than 6 billion requests per second at peak and has more than 10 Exabytes of data under management. Operating at this scale, Bigtable is highly optimized for high-throughput and low-latency reads and writes. Even so, our performance engineering team continually explores new areas to optimize. In this article, we share details of recent projects that helped us push Bigtable’s performance envelope forward, improving single-row read throughput by 20-50% while maintaining the same low latency.

Below is an example of the impact we delivered to one of our customers, Snap. The compute cost for this small-point read-heavy workload reduced by 25% while maintaining the previous level of performance.

Performance research

We use a suite of benchmarks to continuously evaluate Bigtable’s performance. These represent a broad spectrum of workloads, access patterns and data volumes that we see across the fleet. Benchmark results give us a high-level view of performance opportunities, which we then enhance using sampling profilers and pprof for analysis. This analysis plus several iterations of prototyping confirmed feasibility of improvements in the following areas: Bloom filters, prefetching, and a new post-link-time optimization framework, Propeller.

Bloom filters

Bigtable stores its data in a log-structured merge tree. Data is organized into row ranges and each row range is represented by a set of SSTables. Each SSTable is a file that contains sorted key-value pairs. During a point-read operation, Bigtable searches across the set of SSTables to find data blocks that contain values relevant to the row-key. This is where the Bloom filter comes into play. A Bloom filter is a space-efficient probabilistic data structure that can tell whether an item is in a set, it has a small number of false positives (item may be in the set), but no false negatives (item is definitely not in the set). In Bigtable’s case, Bloom filters reduce the search area to a subset of SSTables that may contain data for a given row-key, reducing costly disk access.

We identified two major opportunities with the existing implementation: improving utilization and reducing CPU overhead.

First, our statistics indicated that we were using Bloom filters in a lower than expected percentage of requests. This was due to our Bloom filter implementation expecting both the “column family” and the “column” in the read filter, while a high percentage of customers filter by “column family” only — which means the Bloom filter can’t be used. We increased utilization by implementing a hybrid Bloom filter that was applicable in both cases, resulting in a 4x increase in utilization. While this change made the Bloom filters larger, the overall disk footprint increased by only a fraction of a percent, as Bloom filters are typically two orders of magnitude smaller than the data they represent.

Second, the CPU cost of accessing the Bloom filters was high, so we made enhancements to Bloom filters that optimize runtime performance: 

• Local cache for individual reads: When queries select multiple column families and columns in a single row, it is common that the query will use the same Bloom filter. We take advantage of this by storing a local cache of the Bloom filters used for the query being executed.
• Bloom filter index cache: Since Bloom filters are stored as data, accessing them for the first time involves fetching three blocks — two index blocks and a data block — then performing a binary search on all three. To avoid this overhead we built a custom in-memory index for just the Bloom filters. This cache tracks which Bloom filters we have in our block cache and provides direct access to them.

Overall these changes decreased the CPU cost of accessing Bloom filters by 60-70%.

Prefetching

In the previous section we noted that data for a single row may be stored in multiple SSTables. Row data from these SSTables is merged into a final result set, and because blocks can either be in memory or on disk, there’s a risk of introducing additional latency from filesystem access. Bigtable’s prefetcher was designed to read ahead of the merge logic and pull in data from disk for all SSTables in parallel.

Prefetching has an associated CPU cost due to the additional threading and synchronization overhead. We reduced these costs by optimizing the prefetch threads through improved coordination with the block cache. Overall this reduced the prefetching CPU costs by almost 50%.

Post-link-time optimization

Bigtable uses profile guided optimizations (PGO) and link-time optimizations (ThinLTO). Propeller is a new post-link optimization framework released by Google that improves CPU utilization by 2-6% on top of existing optimizations.

Propeller requires additional build stages to optimize the binary. We start by building a fully optimized and annotated binary that holds additional profile mapping metadata. Then, using this annotated binary, we collected hardware profiles by running a set of training workloads that exercise critical code paths. Finally, using these profiles as input, Propeller builds a new binary with an optimized and improved code layout. Here is an example of the improved code locality.

The new build process used our existing performance benchmark suite as a training workload for profile collection. The Propeller optimized binary showed promising results in our tests, showing up to 10% improvement in QPS over baseline. 

However, when we released this binary to our pilot production clusters, the results were mixed. It turned out that there was overfitting for the benchmarks. We investigated sources of regression by quantifying profile overlap, inspecting hardware performance counter metrics and applied statistical analysis for noisy scenarios. To reduce overfitting, we extended our training workloads to cover a larger and more representative set of use cases. 

The result was a significant improvement in CPU efficiency — reducing fleetwide utilization by 3% with an even more pronounced reduction in read-heavy workloads, where we saw up to a 10% reduction in CPU usage.

Conclusion

Overall, single-row read throughput increased by 20-50% whilst maintaining the same latency profile. We are excited about these performance gains, and continue to work on improving the performance of Bigtable. Click here to learn more about Bigtable performance and tips for testing and troubleshooting any performance issues you may encounter.