This post intend to write down the step for installing ruby and vim command line tools, without root access. In addition, ncurses is the prerequisities of installing ruby and vim. Also, please install ruby first in order to enable rubyinterp.
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Java Performance Os Monitoring
Bottom Up Approach
Bottom up begins at the lowest level of the software stack, at the CPU level looking at statistics such as CPU cache misses, inefficient use of CPU instructions, and then working up the software stack at what constructs or idioms are used by the application.
Choosing the Right CPU Architecture
One of the major design points behind the SPARC T-series processors is to address CPU cache misses by introducing multiple hardware threads per core.
Python Environment Setup
Python is a script language, the main idea for learning python is to utilize python to create easy hands-on automation script on linux env instead of shell.
Here, list the steps to configure PyDev, an eclipse plugin, inside eclipse environment.
Operating System Concepts Io System
I/O Hardware
The device communicates with the machine via a connection point, or port — for example, a serial port.
If devices use a common set of wires, the connection is called a bus. A bus is a set of wires and a rigidly defined protocol that specifies a set of messages that can be sent on the wires.
This figure shows a PCI bus (the common PC system bus) that connects the processor–memory subsystem to the fast devices and an expansion bus that connects relatively slow devices, such as the keyboard and serial and USB ports.
Todo Reading Book List
List the title of the books with corresponding reference url, for those which begin with /* are highly recommended.
Fundamental
Java
- **Thinking in Java (4th Edition) prefer to starting with collections&container chapter
- *Java Performance
- Java Nio
- Java Message Service
Shell
DataBase
Operating System Concepts Virtual Memory
Demand Paging
Loading the entire program into memory results in loading the executable code for all options, regardless of whether an option is ultimately selected by the user or not. An alternative strategy is to load pages only as they are needed. This technique is known as demand paging and is commonly used in virtual memory systems.
Page Fault
A page fault causes the following sequence to occur:
Operating System Concepts Main Memory
Contiguous Memory Allocation
Problem:
Both the first-fit and best-fit strategies for memory allocation suffer from external fragmentation.
The general approach to avoiding this problem is to break the physical memory into fixed-sized blocks and allocate memory in units based on block size. With this approach, the memory allocated to a process may be slightly larger than the requested memory. The difference between these two numbers is internal fragmentation — unused memory that is internal to a partition.
Solution:
Operating System Concepts Cpu
CPU Scheduling
CPU scheduling is the task of selecting a waiting process from the ready queue and allocating the CPU to it. The CPU is allocated to the selected process by the dispatcher.
Scheduling Criteria
- CPU utilization
- Throughput
- Turnaround time
The interval from the time of submission of a process to the time of completion is the turnaround time. Turnaround time is the sum of the periods spent waiting to get into memory, waiting in the ready queue, executing on the CPU, and doing I/O.
- Waiting time
- Response time
Operating System Concepts Process/Thread
Process Control Block
Process Control Block (PCB, also called Task Controlling Block, Task Struct, or Switchframe) is a data structure in the operating system kernel containing the information needed to manage a particular process.
Process state. The state may be new, ready, running, waiting, halted, and so on.
Program counter. The counter indicates the address of the next instruction to be executed for this process.
CPU registers. They include accumulators, index registers, stack pointers, and general-purpose registers, plus any condition-code information. Along with the program counter, this state information must be saved when an interrupt occurs, to allow the process to be continued correctly afterward.