We mount without using noac. I have a file that I append to once every 20 minutes. Then it will be read with mmap about 5,000 times a minute. We only mmap a couple blocks for each read. Needless to say, noac just kills the access performance, so we don't use it.
I add data to the end of the file using a mount with noac and read from a mount without noac. The mounts that are reading are not seeing the new data.
I want to know if there is a function I can call from c to refresh the attributes of a path and all its files.
EDIT: I should add we cannot mount and unmount since there are 16 servers running on each system and they are constantly accessing the files. Well...maybe we could mount and unmount if each server used their own mount. I'd like to avoid that if possible.