hit trafficholder

Analyze the Innodb buffer hit rate calculation from the MySQL source code, innodbbuffer Innodb buffer Hit Ratios is recommended in the official manual for calculation: 100-((iReads / iReadRequests)*100)iReads : mysql->status->Innodb_buffer_pool_readsiReadRequests: mysql->status->Innodb_buffer_pool_read_requests Source: http://dev.mysql.com/doc/mysql-monitor/2.0/en/mem_graphref.htmlSearch "

I recently looked at Apple's official document "event handling guide for IOS", hit-test view in the incident response chain, and a little more understanding, the official document of the individual feel is very simple to this piece, many things are donuts, the knowledge of Hit-test view is used everywhere in the project, but I can not perceive it, and then I will tell you about the three applications that

According to the official manual recommended InnoDB buffer Hit ratios calculation is: 100-((ireads/ireadrequests) *100) ireads:mysql->status->innodb_buffer_pool_reads iReadRequests: Mysql->status->innodb_buffer_pool_read_requests Source: http://dev.mysql.com/doc/mysql-monitor/2.0/en/mem_graphref.htmlSearch "Hit ratios"Recommend interested students to look at this page should also have a great

QUERY Cache organizes the fragments in the cache to get a free block. Qcache_free_memory: Free memory in the cache. Qcache_hits: Increases each time a query is hit in the cache Qcache_inserts: Increases each time a query is inserted. The number of hits divided by the number of inserts is not the ratio. Qcache_lowmem_prunes: The number of times that the cache is out of memory and must be cleaned up to provide space for more queries. This number is

Tags: Running MySQL Status View monitor running MySQL, one way is to view MySQL running status. (1) QPS (query amount per second) QPS = Questions (or Queries)/seconds mysql > show global status Like ' question% '; (2) TPs (transaction volume per second) TPS = (Com_commit + com_rollback)/seconds mysql > show glob Al status like ' Com_commit '; mysql > show global status Like ' Com_rollback '; (3) key Buffer hit rate Mysql>show global Status l

MySQL Cache hit ratio, the online statement is different, below I say my view, everyone tap:The total number of select queries equals Com_select (dead) + qcache_hits (hit) + Parse error query.Let's take a look at the Com_select variable:Mysql>Show Global Status like 'Com_select'; +---------------+-------+ |Variable_name|Value| +---------------+-------+ |Com_select| $ | +---------------+-------+ Com

Running MySQL Status View monitor running MySQL, one way is to view MySQL running status. (1) QPS (query amount per second) qps = Questions (or Queries)/secondsmysql > show global status Like ' question% '; (2) TPS (transaction volume per second) tps = (Com_commit + com_rollback)/Secondsmysql > show global S Tatus like ' Com_commit ', mysql > show global status Like ' Com_rollback '; (3) key Buffer hit rate mysql >show global Status like ' key% ';

your query is small data query, it is easy to create memory fragmentation and waste. Query Cache Fragmentation Rate = Qcache_free_blocks/qcache_total_blocks * 100% If the query cache fragmentation rate exceeds 20%, you can use flush query cache to defragment the cache, or try to reduce the query _cache_min_res_unit, if your query is a small amount of data. Query Cache utilization = (query_cache_size-qcache_free_memory)/query_cache_size * 100% Query Cache utilization below 25% description qu

Simple picture-processing technologyAll pictures Connection: Http://yunpan.cn/cQyWXfIhIUDqX (extract code: 2DB4)Import java.awt.cursor;import java.awt.font;import java.awt.image;import java.awt.point;import java.awt.Toolkit; Import Java.awt.event.actionevent;import Java.awt.event.actionlistener;import Java.awt.event.mouseevent;import Java.awt.event.mouselistener;import Java.util.random;import Javax.swing.imageicon;import Javax.swing.JFrame; Import Javax.swing.jlabel;import Javax.swing.jpanel;imp

2 hours after the database is started, you can use the following SQL to test the database performance. 1. Buffer hit rate: Buffer hit rate indicates the frequency of finding common data blocks in the memory structure without disk access. Select (1-(sum (decode (name, 'Physical reads', value, 0)/(sum (decode (name, 'db block gets', value, 0 ))+ Sum (decode (name, 'consistent gets', value, 0) * 100 "

When a program needs a data in the K+1 layer, d is first searched in its cache K layer. If the data is just in the K-tier, it is called a cache hit.When the end user accesses the accelerator node, it is called a hit if the node has cached the data to be accessed, and if not, it needs to be taken back to the original server, just without a hit.The process of fetching data is synchronized with user access, so even if the new data is re-fetch, the user w

algorithm as when the data is saved. Using the same algorithm, you can select the same server as you saved, and then send a GET command. As long as the data is not deleted for some reason, the saved value can be obtained.This allows the memcached to be distributed by saving different keys to different servers. memcached server, the key will be scattered, even if a memcached server fails to connect, will not affect the other cache, the system can continue to run4.2 remainder distributed algorit

or data that needs to be cached is saved on the server side in the form of a key->value pair. The value of key is converted by hash, and value is passed to the corresponding specific Server according to the hash value. When object data needs to be obtained, it is also based on key. The key is hashed first, and the obtained value determines which server it is stored on, and then makes a request to the server. The client only needs to know which server the value of the hash (key) will be stored o

Springboot2.0+dubbo Aggregation project hit the executable jar packageSpringboot2.0+dubbo-spring-boot-starter Project Server packaging is not the same as the previous version of Dubbo Packaging, do not need to put Dubbo configuration files in the Spring folder under Meta-inf, Similar to regular Springboot project packaging.General Dubbo projects are aggregated form, the following look at the Springboot+dubbo-spring-boot-starter aggregation

Write about the new book, "Write Your Own CPU" blog, this article is mainly to explain the GEM5 to verify the different image of the cache to the cache hit rate effect.The basic cache has been introduced in http://blog.csdn.net/leishangwen/article/details/30049469, which is not repeated here, just a brief introduction.Mainly consists of three major parts: Cache Storage: Stores commands and data blocks that are transferred from main memory.

Internet cache implemented by disks.This topic mainly involves disk caching. Generally, the memory used for caching is easy to lose. If the power supply is cut off, the data stored in the cache will be lost. In this sense, the cache memory is a temporary storage, but the cache used by disk devices and subsystems is non-easy to lose storage. Easy to lose (memory) and non-easy to lose storage relationships This topic is as follows: Cache hit and cache

Several servers in the company are running multiple memcached processes. In addition to monitoring whether the memcached works normally, whether the instance exists, the company also needs to monitor their cache hit rate. Set an alarm for their cache hit rate. There is a perl written on the Internet and needs to be compiled and installed. I wrote a python file and pasted it to run it. I found that the pytho

Calculation method: Select name, (1-(physical_reads/(db_block_gets + consistent_gets) * 100 h_ratio from V $ buffer_pool_statistics; The hit rate, which is used to measure the performance of a database, is already an old man's experience. Now it's all through the Oracle wait interface. The hit rate can be used as a reference, but the hit rate is not necessarily

information needed will be placed in a location that can be accessed as quickly as possible. The concept of caching can be used on several devices, including: • High-Speed memory cache faster than normal memory. • Disk caches that are faster than disk drives and contain memory chips. • Faster Internet access and Internet cache implemented by disks. This topic mainly involves disk caching. Generally, the memory used for caching is easy to lose. If the power supply is cut off, the data stored

OCP question analysis _ 043: buffer cache and hit rate calculation method: www.2cto.com SELECT name, (1-(physical_reads/(db_block_gets + consistent_gets) * 100 H_RATIO FROM v $ ratio; the hit rate, as the standard for measuring the performance of the database, is already an old man's experience. Today, the hit rate can be used as a reference through the oracle wa