Re: sync_file_range()

"ITAGAKI Takahiro" <itagaki.takahiro@oss.ntt.co.jp> wrote
>
>
> I'm interested in it, with which we could improve responsiveness during
> checkpoints. Though it is Linux specific system call, but we could use
> the combination of mmap() and msync() instead of it; I mean we can use
> mmap only to flush dirty pages, not to read or write pages.
>

Can you specify details? As the TODO item inidcates, if we mmap data file, a
serious problem is that we don't know when the data pages hit the disks -- 
so that we may voilate the WAL rule.

Regards,
Qingqing