跳到主要內容

Install K8S on VM and spring boot integration.

Installation Environment Vmware Workstation pro  It is recommended to use the  snapshot  to store the state of each installation stage to avoid installation failures and causing the installation to start from scratch. Ubuntu 22.04 windows 11 Hardware settings  create 3 VM: 4 cores and 4G memory and 100G capacity Before installing K8s (All use the root user) set host: 192.168.47.135 master 192.168.47.131 node1 192.168.47.132 node2 set root ssh connection: sudo su - echo "PermitRootLogin yes" >> /etc/ssh/sshd_config systemctl restart sshd sudo passwd ssh-keygen for i in {master,node1,node2}; do  ssh-copy-id root@$i; done set Ipvs and conf  create conf file: for i in {master,node1,node2}; do ssh root@$i 'cat << EOF > /etc/modules-load.d/containerd.conf overlay br_netfilter EOF'; done execute conf: for i in {master,node1,node2}; do ssh root@$i 'modprobe overlay;modprobe br_netfilter;'; done create 99-kubernetes-cri.conf file: for i in {maste...

Virtual memory

Virtual memory

Separation of user logical memory from physical memory.

  • To run an extremely large process.
    • Logical address space can be much larger than physical address space.
  • To increase CPU/resource utilization.
    • A higher degree of multiprogramming degree.
  • To simplify programming tasks.
    • A free programmer from memory limitation.
  • To run programs faster.
    • Less I/O would be needed to load or swap.

Process & virtual memory

  • Demand paging: only bring in the page containing the first instruction.
  • Copy-on-write: the parent and the child process share the same frames initially, and frame-copy. when a page is written.
    • Allow both the parent and the child process to share the same frames in memory.
    • If either process modifies a frame, only then a frame is copied.
    • COW allows efficient process creation(e.g., fork()).
    • Free frames are allocated from a pool of zeroed-out frames(for security reasons).
      • The content of the frame is erased to 0
  • Memory-Mapped File: map a file into the virtual address space to bypass file system calls(e.g., read(), write())

Page Replacement Concept

  • When a page fault occurs with no free frame
    • Swap out a process, freeing all its frames, or
    • Page replacement: find one currently used and free it
      • Use dirty bit to reduce the overhead of page transfers-only modified pages are written to disk
  • Solve two major problems for demand paging
    • Frame-allocation algorithm:
      • Determine how many frames are to be allocated to a process.
    • Page-replacement algorithm:
      • Select which frame to be replaced
      • Goal: lowest page-fault rate
      • Evolution: running against a string of memory references (reference string) and computing the number of page faults
      • Replacement algorithms:
        • FIFO algorithm.
        • Optimal(Belady) algorithm.
        • LRU algorithm.
      • Counting algorithms:
        • LFU Algorithm(least frequently used).
        • MGU Algorithm(most frequently used).

Thrashing

  • If a process does not have "enough" frames.
    • The process does not have #frames it needs to support pages in active use. -> very high paging activity
  • A process is thrashing if it is spending more time.
  • To prevent thrashing, one must provide enough frames for each process:
    • Working-set model, page-fault frequency
reference:
https://www.amazon.com/-/zh_TW/Operating-System-Concepts-Abraham-Silberschatz/dp/1119800366/ref=sr_1_1?keywords=Operating-System-Concepts&qid=1669538704&s=books&sr=1-1

留言

這個網誌中的熱門文章

Install K8S on VM and spring boot integration.

Installation Environment Vmware Workstation pro  It is recommended to use the  snapshot  to store the state of each installation stage to avoid installation failures and causing the installation to start from scratch. Ubuntu 22.04 windows 11 Hardware settings  create 3 VM: 4 cores and 4G memory and 100G capacity Before installing K8s (All use the root user) set host: 192.168.47.135 master 192.168.47.131 node1 192.168.47.132 node2 set root ssh connection: sudo su - echo "PermitRootLogin yes" >> /etc/ssh/sshd_config systemctl restart sshd sudo passwd ssh-keygen for i in {master,node1,node2}; do  ssh-copy-id root@$i; done set Ipvs and conf  create conf file: for i in {master,node1,node2}; do ssh root@$i 'cat << EOF > /etc/modules-load.d/containerd.conf overlay br_netfilter EOF'; done execute conf: for i in {master,node1,node2}; do ssh root@$i 'modprobe overlay;modprobe br_netfilter;'; done create 99-kubernetes-cri.conf file: for i in {maste...

Mongo DB

Table of contents [ hide ] Mongo DB An open-source NoSQL file database. Due to the use of JSON document data storage structure, MongoDB has three advantages: flexibility, easy expansion, and high performance. Compared with traditional relational databases, users do not need to define the data structure in advance when using MongoDB to store data, and can freely add the Key/Value of the data. Basic concept SQL vs MongoDB Database vs Database Table vs Collection Row vs Document Column vs Field Index vs Index Primary key vs _id View vs View Table Joins vs $lookup Query Syntax Example SQL vs MongoDB a = 1 vs {a: 1} a<> 1 vs {a: {$ne: 1}} a > 1 vs {a: {$gt: 1}} a >= 1 vs {a: {$gte: 1}} a < 1 vs {a: {$lt: 1}} a <= 1 vs {a: {$lte: 1}} Aggregation  Pipeline Stages Description: Mongo DB vs SQL Filter criteria: $match vs where Projection: $project vs as Left outer join: $lookup vs left outer join Sort: $sort vs order by Group: $group vs group by Pagination: $skip/$limi...

OS basic

Table of contents [ hide ] OS architecture The operating system architecture consists of three parts, user mode, kernel mode, and hardware. User mode is for the application to execute the user's program. Kernel mode is to control all the I/O devices and system stability. Storage device hierarchy System call The system call is a kind of software interrupt, including six categories. Process control. File management. Device management. Information maintenance. Communication. Protection. System calls use three methods to pass parameters. Registers. The table in memory. Push onto the stack. A view of operating system services reference: https://www.amazon.com/-/zh_TW/Operating-System-Concepts-Abraham-Silberschatz/dp/1119800366/ref=sr_1_1?keywords=Operating-System-Concepts&qid=1669538704&s=books&sr=1-1