On 2016-06-18 00:23:14 +0600, Aleksey Demakov wrote: > Finally, it's possible to repeatedly mmap > and munmap on portions of a contiguous address space providing > a given addr argument for both of them. The last option might, of > course, is susceptible to hijacking this portion of the address by an > inadvertent caller of mmap with NULL addr argument. But probably > this could be avoided by imposing a disciplined use of mmap in > postgresql core and extensions.
I don't think that's particularly realistic. malloc() uses mmap(NULL) internally. And you can't portably mmap non-file backed memory from different processes; you need something like tmpfs backed / posix shared memory / for it. On linux you can do stuff like madvise(MADV_FREE), which kinda helps. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
