From: Nuutti K. <na...@ik...> - 2005-03-09 15:31:22
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I am wondering what are the memory limits for a single UML guest kernel of 2.6.9-bs7? We are running to some sort of problem just below 500 megabytes already. What is the 2G/2G address space split? What kind of host patches does that require and what are the effects? I could not find any HIGHMEM support style things in configs anymore. TIA, -- Naked |
From: Blaisorblade <bla...@ya...> - 2005-03-09 16:32:21
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On Wednesday 09 March 2005 16:04, Nuutti Kotivuori wrote: > I am wondering what are the memory limits for a single UML guest > kernel of 2.6.9-bs7? We are running to some sort of problem just below > 500 megabytes already. Hmm, in both 2.6.9-bs7 and 2.6.11 the limit is at least 768M, and it extends to more than 2G with static linking and without TT mode. This is all without HIGHMEM support. Retest also with 2.6.11, it feels a better tree than 2.6.9-bs7. What's the problem anyway? > What is the 2G/2G address space split? What > kind of host patches does that require and what are the effects? Probably not interesting for you, it's just a disadvantage for UML, the option was just to cope with that situation (which is completely UML-independent). That gives faster access to upto 2G of physical RAM, by reducing the virtual address space for apps to only 2G rather than 3G. > I could not find any HIGHMEM support style things in configs anymore. That depends on ! CONFIG_CLEAN_COMPILE, so its disappears unless you disable CONFIG_CLEAN_COMPILE... it should compile well in 2.6.11, I don't remember for 2.6.9-bs7. > TIA, > -- Naked -- Paolo Giarrusso, aka Blaisorblade Linux registered user n. 292729 http://www.user-mode-linux.org/~blaisorblade |
From: Nuutti K. <na...@ik...> - 2005-03-09 17:26:13
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bla...@ya... wrote: > On Wednesday 09 March 2005 16:04, Nuutti Kotivuori wrote: >> I am wondering what are the memory limits for a single UML guest >> kernel of 2.6.9-bs7? We are running to some sort of problem just >> below 500 megabytes already. > > Hmm, in both 2.6.9-bs7 and 2.6.11 the limit is at least 768M, and it > extends to more than 2G with static linking and without TT > mode. This is all without HIGHMEM support. The kernels seem to be statically linked by default (or atleast our binaries are). So removing TT mode has beneficial effects if running only on SKAS? Are there any others, except the memory limit raise? > Retest also with 2.6.11, it feels a better tree than 2.6.9-bs7. Okay, will do. Thanks, -- Naked |
From: Blaisorblade <bla...@ya...> - 2005-03-09 20:07:03
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On Wednesday 09 March 2005 18:26, Nuutti Kotivuori wrote: > bla...@ya... wrote: > > On Wednesday 09 March 2005 16:04, Nuutti Kotivuori wrote: > >> I am wondering what are the memory limits for a single UML guest > >> kernel of 2.6.9-bs7? We are running to some sort of problem just > >> below 500 megabytes already. > > > > Hmm, in both 2.6.9-bs7 and 2.6.11 the limit is at least 768M, and it > > extends to more than 2G with static linking and without TT > > mode. This is all without HIGHMEM support. > > The kernels seem to be statically linked by default (or atleast our > binaries are). For TT mode dynamic linking is not possible. > So removing TT mode has beneficial effects if running > only on SKAS? Yes, remember however to enable STATIC linking explicitly. > Are there any others, except the memory limit raise? I don't know... it would be slightly faster and lighter but I doubt it will be measurable. > > Retest also with 2.6.11, it feels a better tree than 2.6.9-bs7. I'm also not sure that 2.6.9-bs7 will compile & work with this config - 2.6.11 should compile and work well, instead, even with STATIC_LINK && ! TT_MODE. > Okay, will do. -- Paolo Giarrusso, aka Blaisorblade Linux registered user n. 292729 http://www.user-mode-linux.org/~blaisorblade |