v1.5.1

This fixes an issue with the recently introduced shared memory on machines with lower total memory. Previously, we always attempted to allocate a static 4GB of virtual memory (this is not physical memory which reflects actual usage). On systems with 4GB or less, this can fail since the OS does not allowing virtual memory that cannot be served by RAM or swap. Now, we check total memory at runtime and reduce the virtual memory allocation if less than 4GB is available.

mmap behavior is platform specific so there could still be some issues with this elastic approach. Please let us know if you see any issues related to memory allocation to help us understand platform behavior better.