Messages in this thread | | | Date | Fri, 21 Jun 2013 15:05:31 -0500 | From | Nathan Zimmer <> | Subject | Re: [RFC 0/2] Delay initializing of large sections of memory |
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On 06/21/2013 12:28 PM, H. Peter Anvin wrote: > On 06/21/2013 10:18 AM, Nathan Zimmer wrote: >>> Since you made it a compile time option, it would be good to know how >>> much code it adds, but otherwise I agree with Greg here... this really >>> shouldn't need to be an option. It *especially* shouldn't need to be a >>> hand-set runtime option (which looks quite complex, to boot.) >> The patchset as a whole is just over 400 lines so it doesn't add alot. >> If I were to pull the .config option it would probably remove 30 lines. > I'm more concerned about bytes of code. Oh, The difference is just under 32k. 371843425 Jun 21 14:08 vmlinux.o /* DELAY_MEM_INIT is not set */ 371875600 Jun 21 14:36 vmlinux.o /* DELAY_MEM_INIT=y */
> >> The command line option is too complex but some of the data I haven't >> found a way to get at runtime yet. > I think that is probably key. > >>> I suspect the cutoff for this should be a lot lower than 8 TB even, more >>> like 128 GB or so. The only concern is to not set the cutoff so low >>> that we can end up running out of memory or with suboptimal NUMA >>> placement just because of this. >> Even at lower amounts of ram there is an positive impact.I it knocks >> time off >> boot even at as small as a 1TB of ram. > I am not surprised. > > -hpa >
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