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The documentation says the following: ROW EXCLUSIVE Conflicts with the SHARE, SHARE ROW EXCLUSIVE, EXCLUSIVE, and ACCESS EXCLUSIVE lock modes. The commands UPDATE, DELETE, and INSERT acquire this lock mode on the target table (in addition to ACCESS SHARE locks on any other referenced tables). In general, this lock mode will be acquired by any ...


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Knowing this, why does sql server need to issue U locks (when using RCSI)? It seems to me that sql server could simply read the rows, and request a X lock directly if an update must be performed. Unlike SI, RCSI does not detect update conflicts. As documented in Books Online, modifying data under RCSI reads currently-committed data, not a possibly ...


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Is there any trace flag enabled or any tweaking into startup parameters of SQL server can you please check that.Have a look at below Microsoft support article http://support.microsoft.com/kb/2199576/en-us Keep max lock value to default EXEC sp_configure 'locks', 0 ( I guess you tried this option already) Now if you face this issue again best possible ...


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The type of locks you are referring to are stored in table (not view) SYS.DBMS_LOCK_ALLOCATED. I believe they only have a "handle", but not a specific owner, i.e.: they all belong to SYS. That said, if you have active blocking situation going on (someone is waiting for the lock and it's not getting released by the session who allocated the lock) then this ...


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Since all the data is MyISAM, you should expect table locks rather frequently since INSERT , UPDATE, and DELETE command issues a full table lock. If you have a lot of tables that use auto increment keys, you should add the following Server1 [mysqld] auto_increment_increment = 5 auto_increment_offset = 1 Server2 [mysqld] auto_increment_increment = 5 ...


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Sounds like you want to consider READ COMMITTED SNAPSHOT ISOLATION, which uses tempdb to provide a point-in-time version of the data and prevents writers from blocking readers and vice-versa (as long as it's ok that readers do not see the most current version of the row). With a table that large and having this much of an impact by concurrent write ...


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You should create your own lock repository CREATE DATABASE IF NOT EXISTS getlock; CREATE TABLE IF NOT EXISTS getlock.lockbox ( conn_id BIGINT NOT NULL, name VARCHAR(64), PRIMARY KEY (name,conn_id) UNIQUE KEY (name) ) ENGINE=MEMORY; Then, whenever you need to create a lock, you perform this sequence SET @lockname = ...



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