Re: [PATCH 0/17] Make O_SYNC handling use standard syncing path (Version 2)

Jamie Lokier
2009-08-22T16:27:15Z

Jan Kara wrote:
> The patch set unifines O_SYNC handling with standard fsync() path. After this,
> we have just one place forcing a single file to disk so filesystems like ext3 /
> ext4 don't have to force a transaction commit in ext?_file_write for O_SYNC
> files / IS_SYNC inodes. The code is also cleaner this way (actually about 150
> lines shorter), we don't sync the inode several times as it happened previously
> etc.

Afaik, O_SYNC requires just the written data to be committed to disk,
but fsync() requires all dirty data for the file (including written by
other processes / descriptors) to be committed to disk.

So doing the equivalent of fsync() after write might be the wrong
thing to do.

-- Jamie