IBM invites CockroachDB to infest its mainframes with PostgreSQL

Vendors promote bridge to modern architecture for legacy systems, but Db2 not going anywhere just yet

IBM has signed an OEM agreement with Cockroach Labs – maker of the distributed PostgreSQL-like cloud RDBMS CockroachDB – in a bid to help modernize mission-critical applications reliant on mainframe hardware.

The alliance aims to offer a cloud-native PostgreSQL database across hybrid environments, including IBM LinuxONE, Linux on Z, Power Systems, and Red Hat OpenShift. The unlikely pair claim that they can help enterprises move to cloud-native and Kubernetes environments without rewriting core applications, though some intermediary components may still be required.

An independent expert on IBM's longstanding RDBMS Db2 told The Register the offering might appeal to Db2 users looking to build new applications in the cloud, but they might be risk-averse in converting existing applications to CockroachDB, a startup founded around ten years ago.

IBM and Cockroach Labs said that, by bringing together fragmented workloads onto CockroachDB on IBM LinuxONE, organizations can simplify operations, reduce risk, and modernize their environment.

Allen Terleto, partners and alliances veep at Cockroach Labs, told The Register IBM was "the best in the industry" at running mission-critical workloads on operational, transactional data in, for example, the financial services industry for the past 40 to 50 years.

"But the world's moving on and starting to deploy greenfield on the cloud," he said.

"There was an appetite for deploying distributed environments on [application platform] OpenShift on x86 and moving to [server] LinuxONE and running potentially Linux on Z mainframe series. They want to be able to run all this in a hybrid manner. The only part of their database portfolio that had a gap was their ability to offer to their customers a PostgreSQL, resilient database."

CockroachDB was designed as a cloud-native database with a distributed file system back end and a front end with near-PostgreSQL compatibility.

While IBM offers a version of Db2 in the cloud, it does not have the same features of either the mainframe Db2 system, or a more modern distributed RDBMS.

"IBM does have a cloud offering on AWS and on IBM cloud as well, but what we're seeing is, for a lot of customers that are going that path, it's really about not disrupting the application side," Terleto said. "It's not necessarily an end state; it's more of a transitory solution which gets them off the mainframe and then sets them up for the modernization to come down the line."

Meanwhile, under the agreement, CockroachDB would also be available on LinuxONE or Linux on Z mainframe. "If a customer wanted to 'modernize in place,' that means they can deploy that on a Linux environment using a distributed, modern database, and in the same way, if they want to move from the mainframe, but not move away from IBM, from a hardware perspective, they can take advantage of LinuxONE," he said.

Terleto said Cockroach Labs was also "doing everything we can to reduce the friction of migration" in moving applications from the mainframe to cloud-native and Kubernetes environments.

He said that the startup was working with "best-of-breed" providers and integrators that have automation technology to "emulate and migrate from these mainframe environments." For example, Rocket Software, which acquired the Application Modernization and Connectivity (AMC) business – formerly part of Micro Focus – from OpenText, could "emulate a COBOL environment and connect that to CockroachDB without you having to make any code changes."

However, Db2 expert and author Craig Mullins said experienced mainframe and Db2 users might be wary of such claims.

PostgreSQL would be an option that many larger enterprise Db2 users would consider as the open source DBMS of choice, and there are companies and tools that purport to help users convert to PostgreSQL. "But it is almost always promoted as data conversion and that is the easy part," Mullins said. "The code conversion is the difficult part. If the conversion can happen without changing code, then that is a benefit. But how? At this point, we have a Db2 application being converted to use CockroachDB with a PostgreSQL compatibility option? That seems like a lot of moving parts already that may or may not work seamlessly. Thinking of the risk-averse nature of IBM customers and my 'I doubt it' radar goes off."

While IBM might be looking to have "multiple irons in the fire" by offering a distributed PostgreSQL, Db2 was not going away on the mainframe or its Linux/Unix/Windows (LUW) iteration. "Db2 is still the DBMS of choice for IBM customers for large enterprise workloads, such as banking," said Mullins, president and principal consultant at Mullins Consulting.

"The CockroachDB partnership is one where IBM can offer a truly, completely distributed cloud-native DBMS," he said. "I do not see IBM Db2 customers – whether Z or LUW – converting their existing applications to CockroachDB, at least for the most part, no matter how easy/hard it might be. That said, IBM customers of LinuxONE building new applications, designed for the cloud/web, could find the usage of CockroachDB – and its supposed compatibility with what they already know – to be an intriguing option. Especially at a lower price point."

From Big Blue to Big Red

Meanwhile, Cockroach Labs has published what it calls an "open benchmark" against Oracle Globally Distributed Database (GDD 23ai) and found CockroachDB to be five times more resilient with less than 30 seconds downtime compared with two minutes for Oracle.

The database company has published a blog post on the setup and invites others to replicate the results and compare other database systems.

"Any benchmarking claims from vendors should be viewed with a pinch of salt, so we made it easy to run the test and see the results yourself as our benchmark methodology is fully documented and open," the post said.

Rob Reid, Cockroach Labs technical evangelist, said: "The code is already within the repo itself, including Oracle GDD, and so are the steps to create a GCP instance on which Oracle GDD can run.

"Oracle did perform well on latency. It's no secret that Oracle have worked hard over the last five decades on making a reliable, high-performance database, and Oracle was consistently seeing requests in the late microseconds to early milliseconds, which is fantastic performance." ®