Molecular biologists use hidden Markov models (HMMs) as a popular tool to statistically describe biological sequence families. This statistical description can then be used for sensitive and selective database scanning, e.g., new protein sequences are compared with a set of HMMs to detect functional similarities. Efficient dynamic-programming algorithms exist for solving this problem; however, current solutions still require significant scan times. These scan time requirements are likely to become even more severe due to the rapid growth in the size of these databases. This paper shows how reconfigurable architectures can be used to derive an efficient fine-grained parallelization of the dynamic programming calculation. We describe how this technique leads to significant runtime savings for HMM database scanning on a standard off-the-shelf field-programmable gate array (FPGA).
HMMer is a commonly used package for biological sequence database searching with profile hidden Markov model (HMMs). It allows researchers to compare HMMs to sequence databases or sequences to HMM databases. However, such searches often take many hours on traditional computer architectures. These runtime requirements are likely to become even more severe due to the rapid growth in size of both sequence and model databases. We present a new reconfigurable architecture to accelerate the two HMMer database search procedures hmmsearch and hmmpfam. It is described how this leads to significant runtime savings on off-the-shelf field-programmable gate arrays (FPGAs).
A method of constructing prerouted FPGA cores, which lays the foundations for a rapid system construction framework for dynamically reconfigurable computing systems, is presented. Two major challenges are considered: how to manage the wires crossing a core's borders; and how to maintain an acceptable level of flexibility for system construction with only a minimum of overhead. In order to maintain FPGA computing performance, it is crucial to thoroughly analyze the issues at the lowest level of device detail in order to ensure that computing circuit encapsulation is as efficient as possible. We present the first methodology that allows a core to scale its interface bandwidth to the maximum available in a routing channel. Cores can be constructed independently from the rest of the system using a framework that is independent of the method used to place and route primitive components within the core. We use an abstract FPGA model and CAD tools that mirror those used in industry. An academic design flow has been modified to include a wire policy and an interface constraints framework that tightly constrains the use of the wires that cross a core's boundaries. Using this tool set we investigate the effect of prerouting on overall system optimality. Abutting cores are instantly connected by colocation of interface wires. Eliminating run-time routing drastically reduces the time taken to construct a system using a set of cores.
Profile hidden Markov models (profile HMMs) are used as a popular bioinformatics tool for sensitive database searching, e.g. a set of not annotated protein sequences is compared to a database of profile HMMs to detect functional similarities. HMMer is a commonly used package for profile HMM-based methods. However, searching large databases with HMMer suffers from long runtimes on traditional computer architectures. These runtime requirements are likely to become even more severe due to the rapid growth in size of both sequence and model databases. In this paper, we present a new reconfigurable architecture to accelerate HMMer database searching. It is described how this leads to significant runtime savings on off-the-shelf field-programmable gate arrays (FPGAs).
HMMER, based on the profile Hidden Markov Model (HMM) is one of the most widely used sequence database searching tools, allowing researchers to compare HMMs to sequence databases or sequences to HMM databases. Such searches often take many hours and consume a great number of CPU cycles on modern computers. We present a cluster-enabled hardware/software-accelerated implementation of the HMMER search tool hmmsearch. Our results show that combining the parallel efficiency of a cluster with one or more high-speed hardware accelerators (FPGAs) can significantly improve performance for even the most time consuming searches, often reducing search times from several hours to minutes.
Systolisation of the pairwise distance computation algorithm and mapping into field programmable gate arrays (FPGA) have proven to give superior performance at a lower cost, compared to the same algorithm running on a cluster of workstations. The primary design methodology for this approach is based on the hardware description languages such as VHDL and Verilog HDL. An alternative design methodology, however, is the use of a high level language such as C to describe the algorithms and generate equivalent hardware descriptions for implementation in FPGA so as to reduce time to market. This paper describes the design and implementation of the ClustalW first stage multiple sequence alignment based on the Smith-Waterman algorithm on a low cost FPGA development platform using a C language development tool suite. Performance evaluation results show that comparable performance could be achieved to that of Pentium 4 systems and other HDL-based solutions using even the smallest commercially available FPGA device with this design methodology.
Profile Hidden Markov Models (PHMMs) are used as a popular tool in bioinformatics for probabilistic sequence database searching. The search operation consists of computing the Viterbi score for each sequence in the database with respect to a given query PHMM. Because of the rapid growth of biological sequence databases, finding fast solutions is of highest importance to research in this area. Unfortunately, the required scan times of currently available sequential software implementations are very high. In this paper we show how reconfigurable hardware can be used as a computational platform to accelerate this application by two orders of magnitude.
This paper explores the use of pre-routed cores as execution objects in an object-oriented programming model and execution environment for dynamic computing on FPGA. In order to maintain FPGA computing performance it is crucial to thoroughly analyze the issues at the lowest level of device detail in order to ensure that computing circuit encapsulation is as efficient as possible. The first methodology that allows a core to scale its interface bandwidth to the maximum available in a routing channel was presented. Cores can be constructed independently from the rest of the system using a framework that is independent of the method used to place and route primitive components within the core. The authors used an architecture model and CAD tools that mirror those used in industry. Abutting cores are instantly connected by co-location of interface wires. Eliminating run-time routing drastically reduces the time taken to construct a system using a set of cores. It was illustrated how, although pre-routing has an adverse impact on core performance by up to 14%, it can improve functional density by up to six times for rapid reconfiguration
Progressive alignment is a widely used approach to compute multiple sequence alignments (MSAs). However, aligning several hundred sequences by popular progressive alignment tools requires hours on sequential computers. Due to the rapid growth of sequence databases biologists have to compute MSAs in a far shorter time. In this paper we present a new approach to MSA on reconfigurable hardware platforms to gain high performance at low cost. We have constructed a linear systolic array to perform pairwise sequence distance computations using dynamic programming. This results in an implementation with significant runtime savings on a standard FPGA.
Molecular Biologists frequently compute multiple sequence alignments (MSAs) to identify similar regions in protein families. Progressive alignment is a widely used approach to compute MSAs. However, aligning a few hundred sequences by popular progressive alignment tools requires several hours on sequential computers. Due to the rapid growth of biological sequence databases biologists have to compute MSAs in a far shorter time. In this paper we present a new approach to MSA on reconfigurable hardware platforms to gain high performance at low cost. To derive an efficient mapping onto this type of architecture, fine-grained parallel processing elements (PEs) have been designed. Using this PE design as a building block we have constructed a linear systolic array to perform a pairwise sequence distance computation using dynamic programming. This results in an implementation with significant runtime savings on a standard off-the-shelf FPGA.
Molecular biologists use Hidden Markov Models (HMMs) as a popular tool to statistically describe protein families. This statistical description can then be used for sensitive and selective database scanning, e.g. new protein sequences are compared with a set of HMMs to detect functional similarities. Even though efficient dynamic programming algorithms exist for the problem, the required scanning time is still very high, and because of the rapid database growth finding fast solutions is of high importance to research in this area. In this paper we present how reconfigurable architectures can be used to derive an efficient fine-grained parallelization of the dynamic programming calculation. It is described how this technique leads to significant runtime savings for HMM database scanning on a standard off-the-shelf FPGA.
Unknown protein sequences are often compared to a set of known sequences (a database scan) to detect functional similarities. Even though efficient dynamic programming algorithms exist for this problem, the required scanning time is still very high. The scan time requirements are likely to become even more severe because of the rapid growth in size of these databases. Thus, finding fast solutions is of high importance to research in this area. We present a new approach to biosequence database scanning using reconfigurable FPGA-based hardware platforms to gain high performance at low cost. To derive an efficient mapping onto this type of architecture, we have designed fine-grained parallel processing elements (PEs) that are tailored towards the parameters of a query. This results in an implementation with significant runtime savings on a standard FPGA.
This paper examines techniques to achieve power, area and configuration storage reductions in the peripherals of a reconfigurable computing system. The two techniques chosen are the propagation of constants to the peripheral core and the modification of the finite state machine (FSM) to reduce switching activity. The constant propagation technique is based on the observation that configuration of peripheral devices is generally set only once during the lifetime of the device. Since the peripheral is running only a single function, the control registers now become redundant, as there is only one input for each of the registers. Removing this eliminates much of the redundant control registers and routines. FSM modification is based on the observation that signal transitions consume power. To reduce the power, the state representations in the FSM are replaced by Gray Code. Gray code only changes one bit at a time, hence, power consumption can be reduced. Results show a reduction in area and configuration storage of up to 20% and a power reduction of up to 7%.
Protein sequences with unknown functionality are often compared to a set of known sequences to detect functional similarities. Efficient dynamic-programming algorithms exist for solving this problem, however current solutions still require significant scan times. These scan time requirements are likely to become even more severe due to exponential database growth. In this paper we present a new approach to bio-sequence database scanning using re-configurable FPGA-based hardware platforms to gain high performance at low cost. Efficient mappings of the Smith-Waterman algorithm using fine-grained parallel processing elements (PEs) that are tailored towards the parameters of a query have been designed. We use customization opportunities available at run-time to dynamically hyper customize the systolic array to make better use of available resource. Our FPGA implementation achieves a speedup of approximately 170 for linear gap penalties and 125 for affine gap penalties as compared to a standard desktop computing platform. We show how hyper-customization at run-time can be used to further improve the performance.
Aligning hundreds of sequences using progressive alignment tools such as ClustalW requires several hours on state-of-the-art workstations. We present a new approach to compute multiple sequence alignments in far shorter time using reconfigurable hardware. This results in an implementation of ClustalW with significant runtime savings on a standard off-the-shelf FPGA.
Summary form only given. Molecular biologists frequently compare an unknown protein sequence with a set of other known sequences (a database scan) to detect functional similarities. Even though efficient dynamic programming algorithms exist for the problem, the required scanning time is still very high, and because of the rapid database growth finding fast solutions is of highest importance to research in this area. We present a new approach to biosequence database scanning on reconfigurable hardware platforms to gain high performance at low cost. To derive an efficient mapping onto this type of architecture, we have designed fine-grained parallel processing elements (PEs). Since our solution is based on reconfigurable hardware, we can design PEs that are tailored towards the parameters of a query. This results in an implementation with significant runtime savings on a standard off-the-shelf FPGA.