Re: Special Kernel Modification

[Ryan Cumming]

On November 4, 2001 21:52, you wrote:
> [e-mail] said:
> > >  Mounting it synchronous will  disable caching in the VM.
> >
> > Who told
> > you that? Synchronous mounting turns off write buffering. Even with
> > "-o sync" writes will still end up in the page cache, they'll just be
> > commited immediately.
>
> Ummm, how about O_DIRECT instead of O_SYNC (or maybe as well, my googling
> hasn't been clear on whether O_DIRECT bypasses the cache on writes as
> well)?
>

Nope, last I checked O_DIRECT enforces buffer and file offset alignment. 
Normal apps wouldn't work very well at all. Maybe UML needs some hacks around 
the whole caching issue?

-Ryan