Programmer Think

Lab System calls Abstract design of physical resources (file system management, memory usage, CPU switching, pipeline interaction); Three states of instruction execution (M,S,U), system call; Macro kernel and micro kernel; Process mechanism (S/U mode, address space, time slice), process purpose (enhancing isolation), process address space and ...

prefaceThis article is about MIT 6 S081-2020-lab8 (lock) implementation;I didn't pass the Buffer cache test when I found the "global optimal solution";Therefore, in Exercise 2, I only provide my various code attempts and ideas on the premise of finding the "global optimal solution";If you find any problems in the content, pl ...

6s081 lab copy on write record This experiment requires the implementation of copy on write. Let's consider what we need to do first Modify the fork to directly copy the contents of the page table of the parent process to the page table of the child process without copying the memory of the parent process when generating the child process. At ...

1. Preface FATFS tutorials and processes are common, and its platforms cover from 8051 core MCU to Cortex-M7 core high-performance MCU and even higher performance application processors. However, most STM32 tutorials and routines bypass this mode using D-Cache writeback mode and DMA. For example, the processes of punctual atoms and wildfire ...

1, Background   when we use the database, we will inevitably encounter the situation that the data is deleted by mistake, which may be business operation errors and code bug s; It may also be an operation and maintenance error, etc; However, we can divide all operations into the following categories: Data loss due to DMLData loss due ...

You will know why interviewers like to ask such questions! One day, Zhang San went to an interview and was asked a question by the interviewer: What is multithreading? Zhang San: multithreading means that multiple threads execute on the CPU, seize CPU resources and improve CPU execution efficiency Interviewer: what are you talking about? W ...

1. Network card binding principle Under normal circumstances, the working mode of the network card is Direct Model. In this mode, the network card only receives frames whose destination address is its own Mac address. Other data frames are filtered out to reduce the burden of the driver. However, the network card also supports another hybrid m ...

This experiment is too, too, too difficult! I can't write it myself. After reading two articles by two big men, I found out. Directly paste the two articles of the boss. One is implemented with an implicit linked list, and the other is implemented with a display linked list. Implicit free linked list The job is compiled into a 32-bit ...

preface Today, we will introduce the relevant knowledge of process control in detail. Such as exit and_ The difference of exit function, the principle of fork function, virtual address space, process creation, process termination, process waiting, process program replacement and so on. Let's study together! 1, Process creation 1.1 in ...

Yesterday, we added a big progress bar to the operating system. Let's continue to make the operating system! Today's main tasks include using structure, text display and starting mouse movement. Use structure to receive startup information (harib02b) The last one was in bootpack In C, 0xa0000, 320 and 200 are written directly into the prog ...