TornadoVM is an open-source framework that enables Java applications to execute on heterogeneous hardware accelerators, such as GPUs and FPGAs. While TornadoVM simplifies programmability, understanding and optimizing the performance of applications on heterogeneous systems remains a significant challenge.

Scaling up the performance of managed applications on Non-Uniform Memory Access (NUMA) architectures has been a challenging task, as it requires a good understanding of the underlying architecture and managed runtime environments (MRE). Prior work has studied this problem from the scope of specific components of the managed runtimes, such as the Garbage Collectors, as a means to increase the NUMA awareness in MREs.

Java benchmarking suites like Dacapo and Renaissance are employed by the research community to evaluate the performance of novel features in managed runtime systems. These suites encompass various applications with diverse behaviors in order to stress test different subsystems of a managed runtime. Therefore, understanding and characterizing the behavior of these benchmarks is important when trying to interpret experimental results.

Although Graphics Processing Units (GPUs) have become pervasive for data-parallel workloads, the efficient exploitation of their tiered memory hierarchy requires explicit programming. The efficient utilization of different GPU memory tiers can yield higher performance at the expense of programmability since developers must have extended knowledge of the architectural details in order to utilize them.

Modern commodity devices are nowadays equipped with a plethora of heterogeneous devices serving different purposes. Being able to exploit such heterogeneous hardware accelerators to their full potential is of paramount importance in the pursuit of higher performance and energy efficiency. Towards these objectives, the reduction of idle time of each device as well as the concurrent program execution across different accelerators can lead to better scalability within the computing platform.

In this work, we propose an approach for transparent compilation and execution of Java programs onto Intel FPGA devices. In detail, we showcase how a managed runtime environment can leverage Intel OpenCL SDK to generate specialized FPGA code, enabling prototyping and acceleration of Java Programs onto FPGAs. Finally, we describe our implementation in the context of TornadoVM with a clear objective to ease FPGA programmability allowing integration with existing frameworks.

By utilizing diverse heterogeneous hardware resources, developers can significantly improve the performance of their applications. Currently, in order to determine which parts of an application suit a particular type of hardware accelerator better, an offline analysis that uses a priori knowledge of the target hardware configuration is necessary. To make matters worse, the above process has to be repeated every time the application or the hardware configuration changes.