You are not able to start more than 4 SSAS tabular model instances with default configuration settings
I have worked on a few cases with this problem. You are not able to start more than 4 SSAS tabular model instances with default configuration settings. The 5th tabular model instance just cannot start unless one of the first 4 instance is stopped.
This is an interesting problem. I found after installing 4 SSAS tabular instances, the 5th instance cannot start until I lower all the instances setting of VeritipaqMemoryLimit to 5. The other configurations do not matter for instances 5 to 8, until the 9th instance.
I am not able to start the 9th instance with all the instances having VertiPaqMemoryLimit=5 LowMemoryLimit=5 MinimumAllocatedMemory=5. So there must be another setting that I need to tweak. As best practice, it is also necessary to change the other memory limits, so I change the HardMemoryLimit, TotalMemoryLimit, and VirtualMemoryLimit as following, then I can start the 9th instance.
<Memory>
<MemoryHeapType>-1</MemoryHeapType>
<HeapTypeForObjects>0</HeapTypeForObjects>
<HardMemoryLimit>10</HardMemoryLimit>
<TotalMemoryLimit>8</TotalMemoryLimit>
<LowMemoryLimit>5</LowMemoryLimit>
<VertiPaqMemoryLimit>5</VertiPaqMemoryLimit>
<MidMemoryPrice>10</MidMemoryPrice>
<HighMemoryPrice>1000</HighMemoryPrice>
<VirtualMemoryLimit>8</VirtualMemoryLimit>
<SessionMemoryLimit>1</SessionMemoryLimit>
<MinimumAllocatedMemory>5</MinimumAllocatedMemory>
<WaitCountIfHighMemory>10</WaitCountIfHighMemory>
<DefaultPagesCountToReuse>2</DefaultPagesCountToReuse>
<HandleIA64AlignmentFaults>0</HandleIA64AlignmentFaults>
<PreAllocate>0</PreAllocate>
<VertiPaqPagingPolicy>1</VertiPaqPagingPolicy>
<PagePoolRestrictNumaNode>0</PagePoolRestrictNumaNode>
<HeapTypeForObjectGroupCount>0</HeapTypeForObjectGroupCount>
<UseCountersPerCPU>-1</UseCountersPerCPU>
</Memory>