If this question is too programmer oriented, let me know.  I wonder if there are people familiar with the O_DIRECT flag for the open() system call on Linux 2.6?  Linus disparages its use, however high performance file writing seems to indicate its use.  I would like to know of any real world experience and recommendations.More info:The application that I am using does maintain its own cache, and in doing so attains an average of 5x or more speed up.  When writing to file, the contents of the cache must be written out to the filesystem cache, which seems redundant and a performance concern.
Use of O_DIRECT on Linux
linux;kernel;files;performance;programming