mstar 4k

~ 1 MB (2^20 * 1 B) G = 0:4k ~ 4GB (2^20 * 4096 B) SSytem flag, if the flag is set, indicates that the key data structure, such as the LDT, is stored in the paragraph, otherwise the segment is a normal data segment or code snippet. TYPEIndicates the type of the segment, as well as access rights. DplDescriptor Privilege Level: Used to restrict access to this segment, indicating the minimum permissions required to access the seg

[i]=1, which is marked as occupied by the page, not the idle bit(5) "Sall $12,%%ecx\n\t"At this time ecx save is mem_map[i] subscript I, that is, the relative number of pages,Example:Suppose Mem_map[0: ( PAGING_PAGES-1)] [last parameter]MEM_MAP[PAGING_PAGES-1] = = 0, i.e. i = = (paging_pages-1),So at this time *ecx = = paging_pages-1;At this point the relative page address is 4k* (paging_pages-1),1024 4-byte physical pages per page, 12-bit left shift

is mem_map[i] subscript I, that is, the relative number of pages,Example:Suppose Mem_map[0: ( PAGING_PAGES-1)] [last parameter]MEM_MAP[PAGING_PAGES-1] = = 0, i.e. i = = (paging_pages-1),So at this time *ecx = = paging_pages-1;At this point the relative page address is 4k* (paging_pages-1),1024 4-byte physical pages per page, 12-bit left shift equals 4096 (2 12-square),(6) "Addl%2,%%ecx\n\t"Add a low-end memory address to get the actual physical addre

is likely due to high CPU utilization, rather than high CPU utilization due to high running queues. The number of active sessions is not particularly high from the database. So next, do you need to focus on whether the system memory management issues are causing high CPU utilization?Reviewing the system memory aspects of/proc/meminfo collected at the beginning of this article, you can find an important piece of data: pagetables:4749076 KB As you can see from the data, the Pagetabl

size can be specified before formatting. But generally not to change. To view the inode size command:650) this.width=650; "src=" Http://s5.51cto.com/wyfs02/M02/86/36/wKiom1e4MwuQFkyTAABDr99Vln4130.png "title=" Snap28.png "alt=" Wkiom1e4mwuqfkytaabdr99vln4130.png "/>A file occupies at least one inode and one block. Block is where the internship holds the content. Block large, will waste disk space, small, affecting disk read performance, general production environment set block size of 4KAsk 100

Each process has its own page table, in Linux, there is a page directory array, which is the top level of the paging mechanism, and each process's page table corresponds to one of the page catalog entries, which can be accessed through the CR3 register.A Process page table that corresponds to the physical address of the page in the page table entry.2. Paging mechanismThe role of paging mechanismThe paging mechanism is performed after the segment mechanism, which further translates the linear add

; # Disables the gzip feature when the client is IE6. Gzip_disable "Msie6"; #Nginx做为反向代理的时候启用. Optional value: Off|expired|no-cache|no-sotre|private|no_last_modified|no_etag|auth|any gzip_proxied any; #设置允许压缩的页面最小字节数, the number of page bytes is fetched from the Content-length in the header header. It is recommended that you set the number of bytes larger than 1k, less than 1k may be more pressing. Gzip_min_length 1024; #设置数据的压缩等级. This level can be any number between 1-9, and

64k;Postpone_output 1460;Open_file_cache max=1000 inactive=300s;Open_file_cache_valid 600s;Open_file_cache_min_uses 2;Open_file_cache_errors off;Include "/usr/local/nginx/conf/vhosts/*.conf";server {Listen 80;server_name _;Access_log off;Location ~*. (Ftpquota|htaccess|asp|aspx|jsp|asa|mdb) $ {Deny all;}Location/{Client_max_body_size 100m;Client_body_buffer_size 128k;Proxy_send_timeout 300;Proxy_read_timeout 300;Proxy_buffer_size 4k;Proxy_buffers 32k

1, the U start installed version of the U disk plug in the computer, and then restart the computer, in the boot screen with a key U-disk to start shortcut keys to start the main menu interface, select "03" Run U start win03pe enhanced version, press ENTER to perform 2, double hit open Diskgenius partition tool, in the Pop-up tool window click to select the partition, and then click the "Delete Partition" button 3, at this point will pop up a prompt to do this will delet

Let's take a look at the details of the U disk: The above is the chip worry-free detection of my U disk information, my U disk capacity of 16GB, total flash memory is also 16GB, the description has not been expanded, is the real 16GB. This is a big thing to worry about. So what's the reason? Let's take a look at it again: Notice that the partition system default is generally Fat32,fat32 is Microsoft's very early file system, but also commonly used in mobile

How to install Win7 on solid State drive I. Installation and preparation 1, solid State hard drive installed on the computer 2, 4G u disk: Making u disk PE boot disk 3, operating system: Win7 64-bit flagship edition 4, startup settings: Set boot from U disk Boot method 5, 4K Alignment Tutorial: SSD Solid State hard disk 4k alignment tutorial 　Second, solid state hard drive mounted Win7 steps as follo

; Gzip_min_length 1k; #最小1K gzip_buffers 64K; Gzip_http_version 1.1; Gzip_comp_level 6; Gzip_types text/plain application/x-javascript text/css application/xml application/javascript; Gzip_vary on; #负载均衡组 #静态服务器组 upstream static.zh-jieli.com {server 127.0.0.1:808 weight=1; } #动态服务器组 upstream zh-jieli.com {sErver 127.0.0.1:8080; #server 192.168.8.203:8080; } #配置代理参数 proxy_redirect off; Proxy_set_header Host $host; Proxy_set_header X-real-ip $remote _addr; Proxy_set_header x-forwarded-f

. The directio_alignment size depends on the file system you use, the default is 512, and for XFS, note that if you do not modify the XFS bsize, you need to adjust to the XFS default 4k. The configuration I used is as follows: Copy Code code as follows: location/archive { Internal AIO on; Directio 4k; Directio_alignment 4k; Output_buffer

is based on the page concept, for example, OS VM1 page is 4K, 4K as long as there is only one element even if only 1 bytes are accessed, the page will not be swap, the same reason, read a byte may be swapped into 4K useless memory. and Redis own implementation can achieve control of the size of the swap. The block process in addition to accessing the operating s

specifies a descriptor that is completed by specifying a descriptive chart and indexing one of the descriptor entries. Segment Registers: The processor saves the information in the descriptor in the segment register, thus avoiding querying the descriptor table every time the memory is accessed. Linear address: indirectly points to the corresponding physical address by specifying a page table, a page in the page table, and an offset value in the page. Page table: An array of simple 32-bit p

specifies a descriptor that is completed by specifying a descriptive chart and indexing one of the descriptor entries. Segment Registers: The processor saves the information in the descriptor in the segment register, thus avoiding querying the descriptor table every time the memory is accessed. Linear address: indirectly points to the corresponding physical address by specifying a page table, a page in the page table, and an offset value in the page. Page table: An array of simple 32-bit p

, and for a specific IO type, the result may be slightly skewed because the speed may be different. By adding ": This option controls the number Sequential produce order of offset Identical produces the same offset [Parameter notes] ' Sequential ' is for random io only. Typically, FIO will generate a new random io after each IO. E.g.rw=randread:8, the seek will be executed after every 8 Io, not after each IO. Sequential Io is already in order and then set to ' sequential ' will not produce any

a normal page (4K), The page number is determined by 31:12 bits of the virtual address. PAE paging If it is a large page (2M), page number is determined by 31:21 bits of the virtual address; if it is a normal page (4K), page number is determined by 31:12 of the virtual address. ia-32e paging If it is a large page (1G), page number is determined by 47:30 bits of the virtual address; if it is a large page (2

achieve hot and cold data separation, Redis only need the OS to request a large memory, the OS will automatically put hot data into physical memory, cold data exchange to the hard disk, another well-known "understanding of the modern operating system (3) Varnish is the realization of this, but also achieved a very successful effect. Author Antirez Several reasons for explaining why he wants to implement the VM himself (6). The main OS VM swapping out is based on the page concept, for example, O

. Quad 0x00cffa000000ffff/*0x23 user 4GB code at 0x00000000*/ Now expand these 4 descriptors:63-60 59-56 55-52 51-48 47-44 43-40 39-36 35-32 31-28 27-24 23-20 19-16 15-12 11-8-7-4 3-0KERNEL_CS:0X00CF9A000000FFFF-->0000 0000 1100 1111 1001 1010 0000 0000 0000 0000 0000 0000 1111 1111 1111 1111KERNEL_DS:0X00CF92000000FFFF-->0000 0000 1100 1111 1001 0010 0000 0000 0000 0000 0000 0000 1111 1111 1111 1111USER_CS:0X00CFFA000000FFFF-->0000 0000 1100 1111 1111 1010 0000 0000 0000 0000 0000 0000 1111 111