04Feb/17

Virtual Memory

February 4, 2017OSdemand-paging, memory, paging, segmentatation, virtual-memoryDreamMaker

A virtual memory is a technique that allows the execution of process that may not be completely in memory. One major advantage of this scheme is that programs can be larger thanRead More…

03Feb/17

Segmentation

February 3, 2017OSpaging, segment-table, Segmentation, segmentation-hardwareDreamMaker

In my previous post, I had discussed about how Paging scheme can be helpful to minimize the amount of fragmentation. In this post I will continue my discussion with segmentation scheme asRead More…

02Feb/17

Paging

February 2, 2017OSmemory-protection, page-table, paging, paging-hardware, PTBR, PTLR, SegmentationDreamMaker

In my previous post I had discussed about “Fragmentation” and how it can be solve. In this and later post, I will discuss some of the memory allocation techniques that can beRead More…

23Jan/17

Fragmentation

January 23, 2017OScompaction, external-fragmentation, fifty-percent-rule, fragmentation, internam-fragmentationDreamMaker

Fragmentation is the primary problem faced while allocating memory. In this article we will focus on Fragmentation and steps to minimize it. Fragmentation can be of two types: Internal Fragmentation External Fragmentation ExternalRead More…

21Jan/17

Contiguous Memory Allocation

January 21, 2017OSbest-fit, contiguous-memory-allocation, first-fit, memory-allocation-techniques, next-fit, worst-fitDreamMaker

In our previous article we had explained about memory protection and in this post we will discuss about memory allocation techniques used by the operating system. This article deals with contiguous memoryRead More…

20Jan/17

Memory Protection

January 20, 2017OSmemory-protection, protection-in-pageDreamMaker

Memory protection is required to ensure that different processes do not mix with each other’s code or data. Every memory address used by a process should be first checked to see whetherRead More…

18Jan/17

Swapping

January 18, 2017OSprocss-swaping, swap-in, swap-out, swappingDreamMaker

A process that need to be executed must be present into the memory. When there is not enough physical memory available for any process or page to be allocated then the operatingRead More…

17Jan/17

Logical and Physical Address

January 17, 2017OSabsolute-address, logical-address-space, logical-and-physical-address, machine-address, memory-management-unit, mmu, relocation-registerDreamMaker

In our previous post we had discussed about different address binding schemes. In this post we will discuss about logical and physical address and address spaces and how operating system deal withRead More…

16Jan/17

Address Binding Schemes

January 16, 2017OSaddress-binding-schemes, compile-time-binding, execution-time-binding, load-time-bindingDreamMaker

In previous post, we had discussed about Interrupt Mechanism performed by operating system. In this post we will look at different address binding schemes used by operating system to generate and manageRead More…

28Dec/16

Interrupt Mechanism

December 28, 2016OSinterrupt-mechanismDreamMaker

The CPU hardware has a wire called Interrupt request line that CPU checks after executing every instruction. When the CPU detects that a device controller has pass a signal on interrupt requestRead More…