Does this memory allocation referres to the physical memory allocated to the node? What's the best way to go about resolving this error?
Its a common issue, if you don't have enough memory (RAM) on nodes
Memory on host xxxxx is overcommitted. The total memory allocation is 107.8 GiB bytes but there are only 62.7 GiB bytes of RAM (12.5 GiB bytes of which are reserved for the system). Visit the Resources tab on the Host page for allocation details. Reconfigure the roles on the host to lower the overall memory allocation. Note: Java maximum heap sizes are multiplied by 1.3 to approximate JVM overhead
First calculate installed services on perticulor node, you can find these details in host Resource tab, then memory section. Now calculate allocated memory, if its maching your total installed memory, you won't get any "Memory Overcommit Validation Threshold" warnings, if its coming morethat what you have memory, then you will get this type of warnings.
You can overcome by doing either reduce service memory or increasing the node memory (RAM)