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On Saturday 27 December 2008 21:13:49 Nikos Chantziaras wrote: |
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> Dale wrote: |
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> > Nikos Chantziaras wrote: |
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> >> On my Gentoo at home, yes. The mouse cursor skips, scrolling gets |
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> >> skippy/laggy too. I have a dual core E6600@3.33Ghz with 4GB DDR2 RAM. |
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> > |
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> > I have to use version 2.6.23-gentoo-r8 for my kernel or it does the same |
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> > thing. Someone mentioned that it is a setting in the kernel for one of |
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> > the new features. At some point I plan to post the info here and try to |
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> > figure out what setting I should use but just haven't done it yet. |
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> > |
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> > The only other thing I can think of is the drives being busy. I think |
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> > they have ionice now too. |
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> |
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> I have this in my make.conf: |
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> |
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> PORTAGE_IONICE_COMMAND="ionice -c 3 -p \${PID}" |
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> |
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> Helped a bit. But still the GUI (KDE 3.5.10) gets pretty laggy. Just a |
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> few hours ago I updated to gcc-4.3.2-r1. Even with nice 19 and ionice |
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> 3, lag is there. |
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> |
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> I hope someone finds the magic button in the kernel config to fix that :P |
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There isn't one - at least not one that really works. |
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Linux mostly ignores NICE and has done so since day one. The reason according |
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to Linux himself on some LKML post quite a while back is that Linux has a |
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semi-decent task scheduler and nice is a 100% manual task scheduler. |
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Therefore nice is not needed. It did have some uses, such as respecting nice |
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settings for having X if set to something very negative - makes gui apps more |
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responsive (X tends to use little cpu and IO time overall but users want it |
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to be responsive). This has largely gone away with Ingo's last task |
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scheduler. |
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On other Unixes, nice has normally been nothing more than a gentle hint to the |
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kernel how the admin would like the systems to treat a certain process. |
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That's why Linux could ignore it and get away with it. |
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You will likely always experience lag compiling something like gcc. It uses |
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gcc to build a new one, and gcc grabs enormous amounts of memory to do this. |
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Plus it's rather disk intensive as well. So, running gcc on a large build is |
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likely to produce lags anyway due to swap and IO no matter how you nice it. |
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More so if resources are constrained. |
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-- |
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alan dot mckinnon at gmail dot com |
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