Distributed lock manager

<p>A distributed lock manager (DLM) runs in every machine in a cluster, with an identical copy of a cluster-wide lock database. <a href="/facts/Operating_system/8XTuvMh2">Operating systems</a> use lock managers to organise and serialise the access to resources. In this way a DLM provides <a href="/facts/Software_application/YQuj7Kog">software applications</a> which are <a href="/facts/Distributed_programming/o5nyhqTF">distributed</a> across a cluster on multiple machines with a means to synchronize their accesses to <a href="/facts/Shared_resource/tmLvfkwR">shared resources</a>.
</p><p>DLMs have been used as the foundation for several successful <a href="/facts/Clustered_file_system/Bz61f7Ce">clustered file systems</a>, in which the machines in a <a href="/facts/Computer_cluster/mT7S1BcX">cluster</a> can use each other's storage via a unified <a href="/facts/File_system/FdPm90uc">file system</a>, with significant advantages for performance and <a href="/facts/High-availability/y3J8GnEo">availability</a>. The main performance benefit comes from solving the problem of <a href="/facts/Cache_coherency/MhUD576q">disk cache coherency</a> between participating computers. The DLM is used not only for <a href="/facts/File_locking/QektVCQs">file locking</a> but also for coordination of all <a href="/facts/Disk_(storage_device)/hnsXRb5X">disk</a> access. <a href="/facts/VMScluster/AUVkB3zp">VMScluster</a>, the first clustering system to come into widespread use, relied on the <a href="/facts/OpenVMS/rAnHAgpD">OpenVMS</a> DLM in just this way.
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Distributed lock manager open-in-new

Distributed lock manager