On Sunday, 8 April 2007 14:56, Pavel Machek wrote: > Hi! > > > Some time ago we discussed the possibility of simplifying the swsusp's > > approach > > towards tracking the swap pages allocated by it for saving the image (so > > that > > they can be freed if there's an error). > > > > I think we can get back to it now, as it is a nice optimization that should > > allow us to use less memory (almost always) and improve performance a bit. > > > > Well, I do not think you can measure the difference, but...
As far as the memory usage is concerned, I can. :-) Usually, it takes 1 extent (40 B on x86_64) to register all of the allocated swap pages. If bitmaps are used, we need as many bits as there are swap pages available (for 1 GB swap and 4 KB pages that would be ~250000 bits, which gives ~8 pages, and we can save more than 800 extents using that much memory). > > kernel/power/power.h | 27 +--------- > > kernel/power/swap.c | 18 +----- > > kernel/power/swsusp.c | 135 > > ++++++++++++++++++++++++++------------------------ > > kernel/power/user.c | 22 +------- > > 4 files changed, 85 insertions(+), 117 deletions(-) > > ....as it removes code... I think we can do that. But it is 2.6.23+ > material. Yes, I think so, but still we can ask Andrew to include it into -mm earlier? ;-) Rafael - 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/
