Messages in this thread | | | Date | Thu, 24 Jun 2004 15:11:30 -0700 | From | Andrew Morton <> | Subject | Re: [discuss] Re: 32-bit dma allocations on 64-bit platforms |
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Andrew Morton <akpm@osdl.org> wrote: > > Note that this code was sigificantly changed between 2.6.5 and 2.6.7.
Here's the default setup on a 1G ia32 box:
DMA free:4172kB min:16kB low:32kB high:48kB active:0kB inactive:0kB present:16384kB protections[]: 8 476 540 Normal free:54632kB min:936kB low:1872kB high:2808kB active:278764kB inactive:253668kB present:901120kB protections[]: 0 468 532 HighMem free:308kB min:128kB low:256kB high:384kB active:87972kB inactive:40300kB present:130516kB protections[]: 0 0 64
ie:
- protect 8 pages from ZONE_DMA from a GFP_DMA allocation attempt
- protect 476 pages from ZONE_DMA from a GFP_KERNEL allocation attempt
- protect 540 pages from ZONE_DMA from a GFP_HIGHMEM allocation attempt.
etcetera.
After setting lower_zone_protection to 10:
Active:111515 inactive:65009 dirty:116 writeback:0 unstable:0 free:3290 slab:75489 mapped:52247 pagetables:446 DMA free:4172kB min:16kB low:32kB high:48kB active:0kB inactive:0kB present:16384kB protections[]: 8 5156 5860 Normal free:8736kB min:936kB low:1872kB high:2808kB active:352780kB inactive:224972kB present:901120kB protections[]: 0 468 1172 HighMem free:252kB min:128kB low:256kB high:384kB active:93280kB inactive:35064kB present:130516kB protections[]: 0 0 64
It's a bit complex, and perhaps the relative levels of the various thresholds could be tightened up. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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