locak

MySQL plus table lock, MySQL server to sense InnoDB plus row lock, in this case, InnoDB to automatically identify the deadlock involving table-level lock; InnoDB will not be able to automatically detect and process this deadlock. (2) in the use of Locak tables to InnoDB lock should be noted that the autocommit is set to 0, or MySQL will not add locks to the table; Before the transaction ends, do not use Unlocak tables to release the table lock, bec

using table locks. (1) using lock Talbes Although it is possible to add a table-level lock to InnoDB, it must be stated that the table lock is not managed by the InnoDB storage engine layer, but is owned by the previous layer of MySQL server, only if autocommit=0, Innodb_table_ Lock=1 (the default setting), the InnoDB layer to know the MySQL plus table lock, MySQL server to sense InnoDB plus row lock, in this case, InnoDB to automatically identify the deadlock involving table-level lock; InnoD

, InnoDB can automatically identify deadlocks that involve table-level locks, otherwise innodb will not be able to automatically detect and process such deadlocks. (2) in the use of Locak tables to InnoDB lock should be noted that the autocommit is set to 0, or MySQL will not add locks to the table; Before the transaction ends, do not use Unlocak tables to release the table lock, because unlock tables implicitly commits the transaction Commit or rol

cache, L2 cache, locak dram, remote dram, Flash, and disk 5. How to migrate code to the primary core "free lunch" Natural Parallelism: quicksort, trees, graphs, hash tables Benefits: faster on multiple cores, making full use of multiple cores Pay: races, deadlocks, cost vs sequential Basic parallel logic: fork-> Run-> join Understanding Scalability: the more cores the faster, the more things you need to consider (memory, I/O

database recovery. Innodb_log_files_in_group = 3 # to improve performance, MySQL can write log files to multiple files cyclically. It is recommended to set it to 3. Innodb_max_dirty_pages_pct = 90 # the InnoDB main thread refreshes the data in the cache pool. Innodb_lock_wait_timeout = 120 # Before InnoDB transactions are rolled back, wait for a lock timeout period. InnoDB automatically detects the transaction deadlock and rolls back the transaction in its own locked table. InnoDB uses the

instance of the author-defined class. Obviously the author does not see how big the difference in the wording. For the use of lock, one of the newcomers asked me this: if I had two static global variables. A parameter value that is used to lock. That is the position of the above Aomilock. The other is inside lock. That is the curly braces inside. So can you change the value inside the lock somewhere else? I can only say sorry to him. can be modified.Note: The above mentioned volatile keyword fa

;+------------------+----------+--------------+------------------+| File | Position | binlog_do_db | binlog_ignore_db |+------------------+----------+--------------+------------------+| mysql-bin.000005 | 49652 | | |+------------------+----------+--------------+------------------+1 row in Set (0.00 sec) Open a Io_thread Threads MariaDB [(None)]> START SLAVE; START SLAVE [io_thread| Sql_thread]; # Start the replication thread , stop using stop Important points

local;2. When you use Locak tables to lock a table, you must also lock all the tables involved, because after locking the current session, you cannot manipulate a table without locks. 4. Concurrent insertion IssuesThe MyISAM storage engine has a system variable, Concurrent_insert, that is specifically designed to control the concurrent insertion behavior, and the value can be 0,1,2. Concurrent_insert is 0, do not allow insertionConcurrent_insert is 1

[HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServiceslanmanserverparameters]> c: delshare. regEcho "AutoShareWks" = dword: 00000000> c: delshare. regEcho "AutoShareServer" = dword: 00000000> c: delshare. regEcho Nowing using the registry file to chang the system default properties.Regedit/s c: delshare. regEcho Deleting the temprotarily files.Del c: delshare. regGoto: END: UsageEcho.Echo ------------------------------------------------------Echo.Echo ☆a example for batch file ☆Echo ☆[ Use batch fi

driver typically returns-efault to the callerAfter calling ACCESS_OK, the data can be transferred safely.You can also use functions that are optimized for the most commonly used data size (1,24,8), which are defined in Put_user (DATUM,PTR)__put_user (DATUM,PTR)When these macro definitions are expanded without type checking, Put_user checks to ensure that the process can write to the specified memory address and returns 0 on success, returning-efault on error. __put_user does less checking (it d

Lab Environment:Centos7_64Experimental objective: To implement the source code installation under Centos7 nginx+mariadb+memcache+php are the latest version--2015.10.10First, to resolve the dependency relationshipYum install-y openssl-devel pcre-devel cmakeSecond, install NginxGroupadd-r NginxUseradd-r-G NginxTAR-ZXVF nginx-1.9.5.tar.gzCD nginx-1.9.5./configure--prefix=/usr--sbin-path=/usr/sbin/nginx--conf-path=/etc/nginx/nginx.conf--error-log-path=/var/log/ Nginx/error.log--http-log-path=/var/lo

methods of accessing ApplicationData, the same Uri can be used to access the above Folder, simply add ms-appdata:///before the path:varLocalFile = Storagefile.getfilefromapplicationuriasync (NewUri (" ms-appdata:///local/some.txt"));varRoamingfile = Storagefile.getfilefromapplicationuriasync (NewUri (" ms-appdata:///roaming/some.txt"));varTempfile = Storagefile.getfilefromapplicationuriasync (NewUri (" ms-appdata:///temp/some.txt"));(3) Credential LockerCredential

instance of the author-defined class. Obviously the author does not see how big the difference in the wording. For the use of lock, one of the newcomers asked me this: if I had two static global variables. A parameter value that is used to lock. That is the position of the above Aomilock. The other is inside lock. That is the curly braces inside. So can you change the value inside the lock somewhere else? I can only say sorry to him. can be modified.Note: The above mentioned volatile keyword fa

, you do not need to manually add or unlock the table, but sometimes you need to display the lock. For example, you can retrieve the number of data in table t1 and table t2 at a certain time point. Common Code: select count (t1.id1) as 'sum' from t1; select count (t2.id1) as 'sum' from t2; In fact, this is not labeled. It is very likely that when you retrieve t1 at that time, the t2 data has changed, that is to say, the t1 and t2 data results you check are not at the same time point. The correct

to be synchronizedBINLOG-IGNORE-DB=DB1,DB2 # Ignore out-of-sync libraries Binlog two parameter 2 Select 1 do not write all syncQuery Bin-log whether to turn on show variables like '%log_bin% '; Grant replication Slave on . to [e-mail protected] ' localhost ' identified by ' 123456 '; # Create a synced userFlush privileges; Show master status; # Be sure to remember the first two columns of content,| File | Position | binlog_do_db |Mysql-bin.0000007 106 4. Do not exit My

backup: #相关mysqldump命令可以mysqldump--help to view#mysqldump--all-database all Library--locak-all-tables lock table (prevent write)3. Now insert data into the database, representing the increment! Show master status; View position value (this value can also be used as a master-slave copy)Numeric value after data is inserted4. Specify the files specified when the binary log is turned on (each flush logs a binary log re-record a new file) so now is the bi

); If no lock is obtained, wait 0.5 seconds for printf ("database is Locak Now,can not write/read.\n"); Each time the callback function is executed once the message is printed, return 1; The callback function returns a value of 1, which attempts to manipulate the database continuously. }The parameter int count is the number of times the callback function was executed, where there is no need for the count value, so there are no operations such as

*1024*1024);Char array[8*1024*1024-1024*10] = {0};}int main (void){pthread_t pid;size_t Stack_size;pthread_attr_t attr;int rc = pthread_create (pid, NULL, THREADFUNC, NULL);if (rc! = 0) {printf ("Create thread failed\n");}Pthread_attr_init (AMP;ATTR);Pthread_attr_getstacksize (attr, stack_size);Stack_size/= 1024 * 1024;printf ("Default Thread stacksize =%dmb\n", stack_size);Pthread_join (PID, NULL);return 0;}2. Thread TLS thread Locak store, thread-pr

-to-const to pass than Passed-by-value.Reason 2: As a user-defined type, its size can easily vary.Reason 3: Using a different C + + compiler may change the size of the type, for example: In some standard library implementationsThe string type is seven times times larger than other versions._______________________________________________________________________________________________________________ _____________________clause 21: When you must return an object, don't be paranoid about returning

: Message mappings for corresponding shortcut keysLresult Cxxxdlg::onhotkey (WPARAM wparam,lparam LPARAM){if (WParam ==1001){MessageBox ("Hotkey F2 already pressed.") ");Here you can add the action you want to perform, or call the button-mapped message function directly}else if (wparam==1002){MessageBox ("Hotkey alt+1 already pressed.") ");}return 0;}Use when closing a dialog boxUnregisterhotkey (GetSafeHwnd (), 1001);/Logoff F2 keyUnregisterhotkey (GetSafeHwnd (), 1002);/Logoff alt+1 keyLog off