Noah Misch <n...@leadboat.com> writes: > On Tue, Apr 24, 2018 at 11:37:33AM +1200, Thomas Munro wrote: >> Maybe try asking what's mapped there with VirtualQueryEx() on failure?
> +1. An implementation of that: > https://www.postgresql.org/message-id/20170403065106.GA2624300%40tornado.leadboat.com Not seeing any other work happening here, I pushed a little bit of quick-hack investigation code. This is based on noting that VirtualAllocEx is documented as rounding the allocation up to a page boundary (4K), but there's nothing specific about whether or how much CreateFileMapping or MapViewOfFileEx might round up. The observed failures could be explained if those guys might eat more virtual address space for the same request size as VirtualAllocEx does. This is a stretch, for sure, but given the lack of any other theories we might as well check it. regards, tom lane
