This memlock flag indicates whether the text segment (the InterSystems IRIS executable code space) is locked in physical memory (on some UNIX platforms). By default, it is not.
This memlock flag indicates whether to disable large/huge pages for shared memory on platforms that support them. By default, large/huge pages are used.
When this flag is off on platforms supporting large pages, InterSystems IRIS attempts to allocate memory in large pages and switches back to standard pages if large pages cannot be allocated at the requested size. Technically, this means that InterSystems IRIS adopts a neutral disposition towards page size, taking no action to request large pages.
This memlock flag indicates whether to require use of large/huge pages for shared memory on platforms that support them (Windows, AIX, and Linux). By default, it is not required. This flag is ignored on other platforms, or if large pages are disabled by the LargePageDisabled flag.
When LargePagesRequired is True (and not ignored), if memory cannot be allocated in large/huge pages, startup is aborted rather than falling back to small pages. InterSystems IRIS retries with a small reduction in memory size, but not as much of a reduction as could occur in absence of this flag.