PostgreSQL, NUMA and zone reclaim mode on linuxLately we've been seeing issues with zone reclaim mode on large memory multi processor NUMA linux systems. What's NUMA? It's just an acronym for Non-Uniform Memory Access. This means that some memory in your system is more expensive for a particular CPU to access than its "local" memory. You can see how much more distant the kernel considers the different zones by using the numactl command like
