350 papers · page 10 of 18
With the availability of chip multiprocessor (CMP) and simultaneous multithreading (SMT) machines, extracting thread level parallelism from a sequential program has become crucial for improving performance. However, many sequential programs cannot be easily parallelized due to th…
We have developed an incremental compacting garbage collector for embedded Java systems. The collector divides the heap into equal sized pages and uses the segregated free lists for fast allocation. Collectors that have such a heap layout have a problem of fragmentation in alloca…
Unrestricted use of heap pointers makes software systems difficult to understand and to debug. To address this challenge, we developed PHALANX -- a practical framework for dynamically checking expressive heap properties such as ownership, sharing and reachability. PHALANX uses no…
Shadow memory is used by dynamic program analysis tools to store metadata for tracking properties of application memory. The efficiency of mapping between application memory and shadow memory has substantial impact on the overall performance of such analysis tools. However, tradi…
The peak heap consumption of a program is the maximum size of the live data on the heap during the execution of the program, i.e., the minimum amount of heap space needed to run the program without exhausting the memory. It is well-known that garbage collection (GC) makes the pro…
C++ has traditionally relied on manual memory management. Sometimes this has been augmented by limited reference counting, implemented in libraries, and requiring use of separate pointer types. In spite of the fact that conservative garbage collectors have been used with C for de…
Good spatial locality alleviates both the latency and bandwidth problem of memory by boosting the effect of prefetching and improving the utilization of cache. However, conventional definitions of spatial locality are inadequate for a programmer to precisely quantify the quality …
In this paper, we investigate the effects of using three different nursery sizing policies on overall and garbage collection performances. As part of our investigation, we modify the parallel generational collector in HotSpot to support a fixed ratio policy and heap availability …
Dynamic binary instrumentation systems are used to inject or modify arbitrary instructions in existing binary applications; several such systems have been developed over the past decade. Much of the literature describing the internal architecture and performance of these systems …
Dynamic memory allocators affect an application's performance through their data layout quality. They can use an application's allocation hints to improve the spatial locality of this layout. However, a practical approach needs to be automatic, without user intervention. In this …
Applications continue to increase in size and complexity which makes debugging and program understanding more challenging. Programs written in managed languages, such as Java, C#, and Ruby, further exacerbate this challenge because they tend to encode much of their state in the h…
This paper introduces a novel set of heuristics for identifying logically related sections of the heap such as recursive data structures, objects that are part of the same multi-component structure, and related groups of objects stored in the same collection/array. When combined …
Precise, flow-sensitive analyses of pointer relationships often represent each object using the set of local variables that point to it (the alias set), possibly augmented with additional predicates. Many such analyses are difficult to scale due to the size of the abstraction and…
It is important that long running server programs retain availability amidst software failures. However, server programs do fail and one of the important causes of failures in server programs is due to memory errors. Software bugs in the server code like buffer overflows, integer…
Tracing algorithms visit reachable nodes in a graph and are central to activities such as garbage collection, marshalling etc. Traditional sequential algorithms use a worklist, replacing a nodes with their unvisited children. Previous work on parallel tracing is processor-oriente…
Magpie is a source-to-source transformation for C programs that enables precise garbage collection, where precise means that integers are not confused with pointers, and the liveness of a pointer is apparent at the source level. Precise GC is primarily useful for long-running pro…
We present a study on data context for object-oriented programs. We first introduce several data structures related to data context that can properly organize object fields, object types and the access sequence in a compact manner. Our approach combines the collection of data con…
This paper presents an analysis that derives a formula describing the worst-case live heap space usage of programs in a functional language with automated memory management (garbage collection). First, the given program is automatically transformed into bound functions that descr…
One of the garbage collectors in Sun's HotSpot "Java" Virtual Machine is known as the generational throughput collector, which was designed to have a large throughput (fraction of time spent on application's work rather than on garbage collection). This paper derives an analytica…
This work presents a technique to compute symbolic polynomial approximations of the amount of dynamic memory required to safely execute a method without running out of memory, for Javalike imperative programs. We consider object allocations and deallocations made by the method an…