Re: Raid resync changes buffer cache semantics --- not good for journaling!

[braam]

Hi,

Stephen wrote:

> Fixing this in raid seems far, far preferable to fixing it in the
> filesystems.  The filesystem should be allowed to use the buffer cache
> for metadata and should be able to assume that there is a way to prevent
> those buffers from being written to disk until it is ready.

What about doing it in the page cache: i.e. reserve pages for journaling
and let them hit the buffer cache only when the transaction allows it?

This may be a naive suggestion, but it looks logical.

- Peter -