On Fri, Aug 14, 2020 at 05:03:44PM +0800, Zhaoyang Huang wrote: > Some system(like android) will turbo read during startup via expanding the > readahead window and then set it back to normal(128kb as usual). However, some > files in the system process context will keep to be opened since it is opened > up and has no chance to sync with the updated value as it is almost impossible > to change the files attached to the inode(processes are unaware of these > things)
Hang on, you're saying that the _only_ way to do turbo-read is the way that userspace currently does it, and userspace cannot be modified, only the kernel? I think somebody has their priorities wrong! > We sync ra->ra_pages with bdi->ra_pages when read. Furthermore, in > consideration > of the scenario of eio and fadvise(...,POSIX_FADV_SEQUENTIAL).We introduce a > seq_read_fact to record the factors of above two cases. No, this is far too complicated.
