On Thu, 5 Apr 2007, Andy Whitcroft wrote: > Christoph if you could let us know which benchmarks you are seeing gains > with that would be a help.
You saw the numbers that Ken got with the pipe test right? Then there are some minor improvements if you run AIM7. I got into this because I saw the code that was generated by sparsemem and discontig. Sparsemem was doing a series of lookups and so did pure discontig on x86_64. Both were really too complex for inlining. Discontig/Vmemmap on IA64 was sort of cleaner but there was still a reference to a variable plus it was creating the needs for lots of TLBs. These VM primitives are pretty critical and the code for those needs to be minimal and inline. So I removed the variable ref from discontig/Vmemmap and reduced the wokr to be done to the simple formula (that I also found in textbooks on memmap management). Avoided the TLB pressure by using the 1-1 mappings page size. I could get real some performance numbers for this by sticking in a performance counter before and after virt_to_page and page_address. But I am pretty sure about the result just looking at the code. - 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/
