cyb70289 edited a comment on pull request #11588: URL: https://github.com/apache/arrow/pull/11588#issuecomment-960425716
Just some tests. FYI. Looks we can advise both `WILLNEED` and `RANDOM` to same memory region (order doesn't matter per my test). I modified test code to only read higher half mapped memory (0.5G ~ 1G). With both `WILLNEED` and `RANDOM` advised, besides random pages scattered in 0.5G ~ 1G, the 0 ~ 1280K memory at the very beginning of mapped memory is also in page cache. No additional useless pages are in os page cache. Looks `WILLNEED` does 10 read aheads from starting address in my test box. Of course, this behaviour is not documented and may be brittle. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
