Messages in this thread | | | Subject | Re: [PATCH] change zonelist order v5 [1/3] implements zonelist order selection | From | Lee Schermerhorn <> | Date | Tue, 08 May 2007 16:37:06 -0400 |
| |
On Tue, 2007-05-08 at 11:05 -0700, Christoph Lameter wrote: > On Tue, 8 May 2007, Lee Schermerhorn wrote: > > > > So far testing is IA64 only? > > Yes, so far. I will test on an Opteron platform this pm. > > Assume that no news is good news. > > A better assumption: no news -> no testing.
Before you asked, yes. I meant after the last message, if you didn't hear from me, everything worked fine. And it does, sort of...
> You probably need a > configuration with a couple of nodes. Maybesomething less symmetric than > Kame? I.e. have 4GB nodes and then DMA32 takes out a sizeable chunk of it? >
I tested on a 2 socket, 4GB Opteron blade. All memory is either DMA32 or DMA. I added some ad hoc instrumentation to the build_zonelist_* functions to see what's happening. I have verified that the patches appear to build the zonelists correctly:
default -> node order, because "low_kmem" [DMA+DMA32] > total_mem/2. Zone lists: DMA: DMA-0 DMA32: DMA32-0, DMA-0, DMA32-1 Normal: same as DMA32 [no normal memory] Movable: same as DMA32 & Normal
explicit zone order also builds as expected: DMA: DMA-0 DMA32: DMA32-1, DMA32-0, DMA-0 and same for normal and movable
However, a curious thing happens: in either order, allocations seem to overflow to the remote DMA32 before dipping into the DMA!!!? I'm using memtoy to create a large [3+GB] anon segment and locking it down.
I need to check a non-patched kernel to see if it behaves the same way, and examine the code to see why... For one thing, the kernel seems to do a bit better at reclaiming memory before overflowing. Eventually, it will dip into DMA and finally get killed--OOM.
I'll be off-line most of the rest of the week, so I probably won't get to investigate much further nor test on a larger socket count/memory system until next week.
Lee
- 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/
| |