On Wed, 7 Mar 2007 01:29:03 -0800 Bill Irwin <[EMAIL PROTECTED]> wrote:
> On Wed, 7 Mar 2007 09:27:55 +0100 Ingo Molnar <[EMAIL PROTECTED]> wrote: > >> btw., if we decide that nonlinear isnt worth the continuing maintainance > >> pain, we could internally implement/emulate sys_remap_file_pages() via a > >> call to mremap() and essentially deprecate it, without breaking the ABI > >> - and remove all the nonlinear code. (This would split fremap areas into > >> separate vmas) > > On Wed, Mar 07, 2007 at 12:35:20AM -0800, Andrew Morton wrote: > > I'm rather regretting having merged it - I don't think it has been used for > > much. > > Paolo's UML speedup patches might use nonlinear though. > > Guess what major real-life application not only uses nonlinear daily > but would even be very happy to see it extended with non-vma-creating > protections and more? uh-oh. SQL server? > It's not terribly typical for things to be > truncated while remap_file_pages() is doing its work, though it's been > proposed as a method of dynamism. It won't stress remap_file_pages() vs. > truncate() in any meaningful way, though, as userspace will be rather > diligent about clearing in-use data out of the file offset range to be > truncated away anyway, and all that via O_DIRECT. The problem here isn't related to truncate or direct-IO. It's just plain-old MAP_SHARED. nonlinear VMAs are now using the old-style dirty-memory management. msync() is basically a no-op and the code is wildly tricky and pretty much untested. The chances that we broke it are considerable. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
