2016-01-07 balloon set_config invoke

balloon set_config invoke

Modern Operating System: Memory Management

No Memory Abastraction

• 单进程
• 多进程：页机制，PSW，保护位，静态重定位
• 在嵌入式系统中，依然有很多没有内存抽象

A Memory Abstraction:Address Spaces

Two problems:protection and multi-process

• The Notion of an Adress Space:Base and Limit Registers,dynamic relocation
• Swapping:memory compaction
• Managing Free Memory
  
  • bitmaps
  • linked lists:first fit,next fit,best fit,worst fit,quick fit

• Virtual Memory

  • Paging:MMU,pages,page frames,present/absent bit,page fault,page table
  • Page Tables:Empty,Caching disabled,Referenced,Modified,Protection,Present/absent,Page frame number

  • Speeding Up Paging:fast,and page table is small

    • Translation lookaside buffers:TLB
    • Software TLB Management:less miss,and quick deal miss;software cache
    • soft miss,hard miss
  • Page Tables for Lage Memories:multi-level page tables,inverted page tables
• Page Swapping Algorithm
  
  • optimal
  • NRU,FIFO,Second Chance,Clock
  • LRU,NFU,Aging
  • Working set,WSClock

vim 取消高亮

:nohl

QEMU

Enter QEMU console

Ctrl+a c

balloon set_config invoke

qemu/build/x86_64-softmmu/hmp-commands.h    这种全是{}，的头文件是用来做什么的？里面的赋值很像是json    {    .name       = "balloon",    .args_type  = "value:M",//此处value依然为MB数    .params     = "target",    .help       = "request VM to change its memory allocation (in MB)",    .mhandler.cmd = hmp_balloon,    },qemu/hmp.c    hmp_balloon()        qmp_balloon(value, &err);//此处的value应该已经转换为字节数为单位了qemu/balloon.c    qmp_balloon()        balloon_event_fn(balloon_opaque,target);    QEMUBalloonEvent *balloon_event_fn    qemu_add_balloon_handler()        balloon_event_fn=event_func;qemu/hw/virtio/virtio-balloon.c    virtio_balloon_device_realize()        ret = qemu_add_balloon_handler(virtio_balloon_to_target,virtio_balloon_stat, s);    virtio_balloon_to_target()        ram_addr_t vm_ram_size = get_current_ram_size();        if (target > vm_ram_size) {            target = vm_ram_size;        }        if (target) {            dev->num_pages = (vm_ram_size - target) >> VIRTIO_BALLOON_PFN_SHIFT;            virtio_notify_config(vdev);        }

USACO Training

USACO新增了三道题目，借此机会在Github建立了algorithm，并且把以前的USACO代码上传了上去。

Memcached

forked memcached, and wget & compiled memcached-1.4.5

随笔

现在流的泪，都是当年脑子进的水。

简单的grep自己都没好好学，找balloon的入口都费了老半天劲，最后还是韬神过来几下就搞定了。知耻而后勇，既然知道了自己的不足，那就抓紧赶上。平时的闲暇时间要找出以前的讲义、作业重新掌握。