westinghouse 4k

(for memory concepts):is usually a multiple of 64K.Spare: Not usedPrivate: BookedImages: Storing codeMapping: Storing data2. Physical memoryThe system can use the actual memory, the CPU can directly access the memory3. Virtual memoryVirtual memory data must be placed into physical memory when the CPU assumes access to virtual memory data by virtualizing the hard disk files into intrinsic use (Pagafile.sys).4. Memory page (for address concept)The smallest unit of system management memory. The me

); } ?> In addition, we also need to note that the refresh buffer is not only affected by the above aspects, but also by the following: 1) Some web server programs, especially the web server programs under Win32, will cache the Script output until the program ends before sending the results to the browser. Some Apache modules, such as mod_gzip, May output the cache by themselves, which causesFlush ()The results produced by the function are not immediately sent to the client browser. Even the b

does not display the entire table until the 2). The effect of PHP installation mode. The above method can be used directly in the case of PHP installed in Apache module mode. If you need to pay attention to the following configuration in the fastcgi way: a). apache+fcgid+phpFcgidoutputbuffersize 0 (default is 65536) When you configure Fcgid, this value is set to 0, and the above code does the refresh buffer to achieve its desired effect. b). iis+fastcgi+php Responsebufferlimit=0 Modify this it

for hard disks: MBR and GUID (GPT)MBR: Master boot record, supports up to 4 primary partitions, identifies up to 4G of single hard DrivesFile system formats: NTFS and FAT32Hard Drive 4K Alignment:A file 1K also takes up 4K of space.NTFS format is 4K is a cluster, the original hard disk sector is 512 bytes, in order to align the NTFS cluster, the hard disk format

operating system provides a virtual process space for each process, on a 32-bit operating system, the size of the process space is 4g,64-bit system 2^64 (which may actually be less than this value). For a long time, I was very puzzled about this, so that does not lead to multiple processes to visit the conflict, for example, two processes are access to address 0x00000010. In fact, the process space for each process is virtual, which is not the same as the physical address. The two are accessing

this, but also achieved a very successful effect.Author Antirez Several reasons for explaining why to implement the VM himself (6). The main OS VM swap out is based on the page concept, such as OS VM1 page is 4K, 4K as long as there is an 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 of

The most common physical unit on a disk is a sector, and a disk consists of a number of sectors.The sector size of an older disk is 512 bytes.CHS and LBA are two ways of addressing a disk and are now used in LBA mode.The LBA method is simple, and all sectors are numbered starting at 0, and the location of the sector is specified by the number of mountains.With Fdisk-lu, you can see the number of slices of a disk and its partitions.Sector number NO. 0 is the sector that stores the MBR.In MBR 0-44

time.Reset_timedout_connection on; #告诉nginx关闭不响应的客户端连接. This will release the memory space occupied by that client.Send_timeout 10; #指定客户端的响应超时时间. This setting is not used for the entire forwarder, but between two client read operations. If, during this time, the client does not read any data, Nginx closes the connection.AutoIndex on; #开启目录列表访问, the appropriate download server, the default shutdown. Client_header_buffer_size 32k; #客户端请求头部的缓冲区大小, this can be set according to your system paging s

CI nginx Rewrite rules server {Listen 80;server_name ttlsa.com www.ttlsa.com;root/data/site/www.ttlsa.com;Index index.php;Error_log Log/error.log;# Set expiration of assets to MAX for cachingLocation ~*. (ico|css|js|gif|jpe?g|png) (? [0-9]+)? $ {Expires Max;Log_not_found off;}# main CodeIgniter rewrite ruleLocation/{Try_files $uri $uri//index.php;}# PHP parsingLocation ~. php$ {root/data/site/ttlsa.com/;Try_files $uri = 404;Fastcgi_pass Unix:/tmp/php5-fpm.sock; # changed to the corresponding fas

=" consider using RAID 50 to replace raid ten (SSD) "style=" Border:0px;vertical-align:middle;height:auto; />RAID 50 in the above comparison has been able to tolerate the 3rd or even 4th disk failure, but the availability is lower than raid 10, but neither of them can achieve the perfect 100%, so the tradeoff between availability and cost of RAID 50 is a considerable advantage.Next look at performance, in order to be able to analyze performance well, we followed the first set of comparison scena

Recent program error: Failed to connect to Redis:connection timed outFind information about THP, decide to test and modify1.page and Huge PagesPageIn general, memory management of the minimum block-level units called page, a page is 4096bytes,1m memory will have 256 PAGE,1GB words will have 256,000 page.The CPU maintains the page table record through the built-in memory management unit.Huge Pages:Huge pages is a 2M to 1GB memory page, mainly used to manage thousands of trillion of memory, such a

1 2 4 8 Ten - - + +; DoSysbench--test=fileio--file-TOTAL-SIZE=256G--file-test-mode= $rwtype--max- Time= ---max-requests=0--file-BLOCK-SIZE=4K--file-num= ---num-threads= $numthread run >> $result _dir/Io_${rwtype}_thread${numthread}.txt; Sleep Ten; Done Done#-----------------------------CPU Test-------------------------------- foreachinch 1`seq 2 2 +`; DoSysbench--test=cpu--cpu-max-prime=40000--num-threads= $each run >> $result _dir/Cpu_thread

/error.log; #gzip compressed transport gzip on; 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 _a

configuration:Fastcgi_buffers # control Nginx create up to 8 buffers with a size of 4K fastcgi_buffer_size # processing The size of the first buffer when Response is not included in the formerThe maximum memory buffer size that can be created by total is 8*4k+4k = 36kWhen Response is less than or equal to 36k, all of the data is, of course, processed in me

Chengdu 2. What level does 5k PHP programmers need Like the title--I learned PHP for almost 2 months, has not written a lot of code Recently learned Html,css, PHP JavaScript then level anyway is not high. And didn't want to get a high salary. I asked you last time. I am now a 4k C + + QT Programmer I want to find a PHP job after leaving, but know that their level is not enough to break the study On the weak weak ask PHP salary structure is what level

also read the original analysis to understand other conclusions that can be obtained.It is not difficult to see that every 1024 steps in the figure, that is 1024*4 , 4096Bytes each, has a particularly obvious blue vertical line. That is, as long as we follow the 4K step into the memory (memory according to 4K alignment), no matter how big the hot data it's actual efficiency is very low! According to our an

~ 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