On Sat, Dec 23, 2006 at 10:09:57PM +0300, Alex Tomas wrote: > > Good day, > > >>>>> David Chinner (DC) writes: > > DC> So that mean's we'll have 2 separate mechanisms for marking > DC> pages as delalloc. XFS uses the BH_delay flag to indicate > DC> that a buffer (block) attached to the page is using delalloc. > > well, for blocksize=pagesize we can save 56 bytes on every page. Sure, but it means that ext4 w/ delalloc won't work on lots of machines.... > DC> FWIW, how does this mechanism deal with block size < page size? > DC> Don't you have to track delalloc on a block basis rather than > DC> a page basis? > > I'm still thinking how better to deal with that w/o much code duplication. Code duplication in ext4, or across all filesystems? > DC> Ah, that's why you can get away with a page flag - you've ignored > DC> the partial page delay state problem. Any plans to use the > DC> existing method in the future so we will be able to use ext4 delalloc > DC> on machines with a page size larger than 4k? > > what do you mean by "exsiting"? BH_delay? Yes. Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group - To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
