On 06/23/2013 02:32 AM, Ingo Molnar wrote: > > * Ingo Molnar <mingo@xxxxxxxxxx> wrote: > >> Yet another thing to consider would be to implement an initialization >> speedup of 3 orders of magnitude: initialize on the large page (2MB) >> grandularity and on-demand delay the initialization of the 4K granular >> struct pages [but still allocating them] - which I suspect are a good >> chunk of the overhead? That way we could initialize in 2MB steps and speed >> up the 2 hours bootup of 32 TB of RAM to 14 seconds... >> >> [ The cost would be one more branch in the buddy allocator, to detect >> not-yet-initialized 2 MB chunks as we encounter them. Acceptable I >> think. ] > > One advantage of this scheme would be that we could use it on pretty much > any box, it would provide instant boot time speedups everywhere [a couple > of hundred msecs on a small 4GB box - significant I think] - and would > spread out and parallelize initialization to later stages. > Even better if we could start at the 1 GB level, which most of these really huge machines will have hardware support for. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
