Legacy is a class of computing that retains its value. These systems and applications were usually developed 10 years ago and more, but they remain vital. Some of that vitality is a result of relying on Oracle. The database is solid, proven. The hardware that drives Oracle can get long in the tooth, though. Eventually that means a legacy migration — but it only has to be to fresher hardware. Oracle remains your bedrock, if you know how to emulate.
Many legacy apps are custom applications, and some use Solaris and SPARC hardware no longer supported by the system vendor. The question is not if the hardware's going to fail, but when? To get away from the older hardware risks, Oracle users do hardware emulation. It can be an intermediate solution while rewriting an application or updating Oracle. Or it can be long-term, especially if people need data for archival purposes.
I’m going to share what we’ve learned in studies with Oracle users. These are datacenters with IT managers who we’ve helped retain Oracle as their centerpiece. They continue to rely on Solaris, too.
In our first case study, our customer was migrating both legacy apps and the Oracle database using the Stromasys Charon-SSP emulator. In an another article, we’ll look at migrating just legacy apps using the emulator, while the Oracle database is brought over separately to an x86 version for Windows or Linux.
Oracle and apps migrated
In our first case, a company in the manufacturing sector migrated applications as well as its Oracle database. The target was a single emulator instance hosted in the cloud. This manufacturer had used on-premise hardware as well as VMware VMs.
From a physical standpoint, the emulator can be implemented on top of either physical or virtual hardware. Using virtual hardware gives you flexibility, availability, and security options. Scalability comes along with virtualization, too.
Although virtualized hosting is great, using physical hardware gives you an additional measure of performance. You may have to forego some of the advantages of virtualizing in order to get the performance needed for really heavy workloads.
This manufacturer chose to use our Charon-SSP, emulating SPARC. The database connections were local to the SPARC machine between the applications and the Oracle database. We began by assessing the legacy system. Stromasys provides utilities to profile the workload. The Oracle database and all the applications were competing for CPU resources, as well as memory and disc IO.
All of the processors on the SPARC server were utilized at 100 percent from 5 PM to 8 AM the next day while reports ran. During the nine-hour workday, utilization was between 70-80 percent. So this server was crushed almost all the time, even on the weekends. We took great care to ensure we provided sufficient performance on the target system.
We then examined the Oracle version to see about unusual data types, or external procedures that were specific to that version of Solaris. Those custom apps had the connect strings for the Oracle database hard-coded into the application.
At the datacenter, the manufacturer’s team determined there wouldn’t be enough time to modify the application code to point to a new database server. The team had to keep things as originally configured for the SPARC platform.
We configured a target platform that would perform well enough to make this application work — and even provide room for scalability for growth. The server used two Intel Xeon Gold processors. That’s a really good go-to for emulators, because of the balance of the number of cores versus the base and max turbo frequency of the processors. We made that server a dedicated host to get performance benefits, because this workload was just so intense.
The Oracle database and all applications remained on the same server. So that made the migration piece actually fairly easy. To do this, we used a flash archive, a bit-for-bit copy of the installation of Solaris and all the installed applications and database servers. We lifted it off the old platform, installed it on the new platform, and ran tests.
At the end of the migration, the customer had a dedicated physical host running Linux with the Charon SPARC emulator installed. It ran everything from the Solaris layer up. That meant that Solaris, and the Oracle database and the applications, were moved directly to the SPARC emulator. Oracle is your steady value in your datacenter. When legacy applications run your business, you can do a cost-effective lift and shift migration, using emulation.