Re: [PATCH] Apply memory policies to top two highest zones when highest zone is ZONE_MOVABLE

[Lee Schermerhorn <Lee.Schermerhorn@hp.com>]

On Thu, 2007-08-02 at 18:21 +0100, Mel Gorman wrote:
> The NUMA layer only supports NUMA policies for the highest zone. When
> ZONE_MOVABLE is configured with kernelcore=, the the highest zone becomes
> ZONE_MOVABLE. The result is that policies are only applied to allocations
> like anonymous pages and page cache allocated from ZONE_MOVABLE when the
> zone is used.
> 
> This patch applies policies to the two highest zones when the highest zone
> is ZONE_MOVABLE. As ZONE_MOVABLE consists of pages from the highest "real"
> zone, it's always functionally equivalent.
> 
> The patch has been tested on a variety of machines both NUMA and non-NUMA
> covering x86, x86_64 and ppc64. No abnormal results were seen in kernbench,
> tbench, dbench or hackbench. It passes regression tests from the numactl
> package with and without kernelcore= once numactl tests are patched to
> wait for vmstat counters to update.
> 
> Signed-off-by: Mel Gorman <mel@csn.ul.ie>


And an ia_64 NUMA platform with some ad hoc, interactive functional
testing with memtoy and an overnight run of a usex job mix.  Job mix
included a 32-way kernel build, several povray tracing apps, IO tests,
sequential and random vm fault tests and a number of 'bin' tests that
simulate a half a dozen crazed monkeys pounding away at keyboards
entering surprisingly error-free commands.  All of these loop until
stopped or the system hangs/crashes--which it didn't...


Acked-by:  Lee Schermerhorn <lee.schermerhorn@hp.com>
Tested-by:  Lee Schermerhorn <lee.schermerhorn@hp.com>