boost - Shared memory alignment in C++ -


is there alignment allocated shared memory? if yes, operating system?

for example, allocating shared memory in boost:

boost::interprocess::shared_memory_object* segment =     new boost::interprocess::shared_memory_object(         boost::interprocess::create_only,         "name",         boost::interprocess::read_write);  segment->truncate(10000);

the shared/virtual memory system allocates , maps memory pages , aligned page size. see list of pages sizes here. page size cpu , os specific. not aware of modern cpus use page sizes smaller 4kb.

on posix system can find out page size using sysconf(_sc_pagesize). in case when huge pages in use, call returns smallest page size.


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