Semispace, Operating System

Semispace works by maintaining two disjoint areas from which memory can be allocated. These areas are called the from-space and the to-space. At ?rst, the algorithm allocates memory only from the from-space, without ever worrying about garbage collection. Allocation then is typically performed using simple pointer bumping, which simpli?es the whole process a lot. When we ?nally run out of space in the from-space, we sweep through all allocated objects that can be somehow reached; those are the ones that are still live. We then move each of these live objects to the to-space, taking care to update all pointers to the live objects to point to its new location in the to-space. Hence semispace is called a copying collector. After having done all this moving, only live objects are in the to-space. From this moment on, we can start using the to-space to perform allocation. The process is repeated again when the to-space eventually runs out of space. Thismethod has as advantages the fact that it might "compact" objects in the memory, thus increasing locality and minimizing fragmentation. Also, when performing allocation from one of the spaces, it can use simple pointer bumping, which is very fast. However, this approach doubles the memory requirements.

Posted Date: 3/13/2013 2:57:31 AM | Location : United States







Related Discussions:- Semispace, Assignment Help, Ask Question on Semispace, Get Answer, Expert's Help, Semispace Discussions

Write discussion on Semispace
Your posts are moderated
Related Questions
What are threads? A thread - sometimes called as an implementation context or a lightweight process - is a single sequential flow of control within a program. We use threads

Task 1 description: Design and implement the disableuser.sh script. Required script functionality: disableuser.sh -v : prints the script version number and exits dis

Now, let us discuss two related algorithms for deciding which pages to evict. The clock algorithm is one of the most popular choices. It works by keeping frames in a circular struc

Q. Why might a system utilize interrupt-driven I/O to manage a single serial port however polling I/O to manage a front-end processor such as a terminal concentrator? A

Q. Describe why SSTF scheduling tends to favour middle cylinders over the innermost and outermost cylinders. Answer: The middle of the disk is the location having the smalles

Question: OS Installation / File system a) Why is NTFS portioning preferred over FAT16 or FAT32 when security is of primary concern? b) State a situation or an application w

Explain the various page replacement strategies. Page replacement-basic scheme with diagram Optimal page replacement LRU page replacement FIFO page replacement LRU

What are the various scheduling criteria for CPU scheduling? The various scheduling criteria are CPU utilization

In fixed portioning scheme, what are the advantages of using unequal- size partitions? With unequal-size partitions there are two probable ways to assign process to partitions.

Describe the internal layout of the file system in windows 2000. The basic entity in NTFS is a volume and a volume is created by the Windows 2000 disk administrator utility and