Re: 2.4: mylex and > 2GB RAM

[William Lee Irwin III]

William Lee Irwin III <wli@xxxxxxxxxxxxxx> writes:
>> If your memory ended at 2GB and the driver had 31-bit DMA, it may have
>> decided to use unconstrained allocations. Then, when you added more RAM,
>> it was forced to ask for <= 896MB, which made it copy to buffers that are
>> actually below 896MB most of the time.

On Mon, Dec 08, 2003 at 09:15:15PM +0100, Per Andreas Buer wrote:
> But this would reduce the throuput only a few percent, right? My system
> slows down from writing ~ 100MB/s to maybe 50KB/s. 

It could potentially slow it down a lot more than a few percent.

The main effect you would see is heavy low memory consumption (LowFree:
going down to almost nothing) and very heavy cpu consumption.


-- wli
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