Need details on the nodes and Semaphore

[hamanthk]

I read the docs but did not understand nodes and semaphore concept.  Can someone help me with a simplified concepts of these.

[HarshitaN]

Hello @hamanthk 

Nodes:
A node is simply one server that runs part of your ServiceNow instance. Multiple nodes work together as a cluster. They share user requests, background jobs, workflows, and integrations.
You can think of nodes as multiple workers handling tasks in parallel, so the instance is fast and highly available.

Semaphores:
A semaphore is a lock that prevents two nodes from running the same job at the same time.
When a scheduled job or background process starts, it tries to take a semaphore. If the lock is available, the job runs on that node. If another node already holds the lock, the job waits or skips.
This prevents duplicate execution, data conflicts, and race conditions in a multi-node setup.

Regards, 
Harshi Negi

[Ankur Bawiskar]

@hamanthk 

did you check these?

Information about Semaphore and Scheduler Workers 

System Resources 

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[Ankur Bawiskar]

@hamanthk 

Hope you are doing good.

Did my reply answer your question?

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[nazimhusain]

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