Qlik Sense repository service goes down and logs show inconsistency Type "CT” errors

Occasionally the Qlik Sense repository service goes down and the  logs show inconsistency Type "CT” errors as below.

Inconsistency Type "CT” indicates a  "Cache Trimmer"  error, which means that when  the Engine trims the cache for releasing memory, it has encounters an unexpected exception. 

The root cause varies, but most likely it has something to do with low resources memory.

For servers with memory such as 8 GB memory is considered very low. It is highly recommend to upgrade the server memory at least to 32 GB. This will guarantee that the server  have enough resources to stay responsive and clear the cache in a more efficient way while users are still accessing the server.

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2037 20171211T120427.406+0800 INFO IMDA17QLIKPVW01 System.Engine.Engine 10 0881add5-b989-4693-9d48-6dc05840b4bd .\QVadmin Engine: Server aborted. Reason for restart: Internal inconsistency, type CT, detected. 0 Internal Engine 20171211T120427.411+0800 3552 4784 20171204T142535.000+0800 0881add5-b989-4693-9d48-6dc05840b4bd

2038 20171211T120427.422+0800 ERROR IMDA17QLIKPVW01 System.Engine.Engine 26 334ee237-6c09-4ec1-b213-ec9394f84465 .\QVadmin Restart: Server aborted trying to recover by restart. Reason for restart: Internal inconsistency, type CT, detected. 0 Internal Engine 20171211T120427.413+0800 3552 4784 20171204T142535.000+0800 334ee237-6c09-4ec1-b213-ec9394f84465

2039 20171211T120428.406+0800 WARN IMDA17QLIKPVW01 System.Engine.Engine 26 16af8479-3919-4074-b55f-475ca5cea3b4 .\QVadmin Server: CPurger: Thread failure 0 Internal Engine 20171211T120428.412+0800 3500 4784 20171204T142535.000+0800 16af8479-3919-4074-b55f-475ca5cea3b4