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On Saturday 17 September 2005 02:32, Alec Warner wrote: |
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> Jason Stubbs wrote: |
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> > On Saturday 17 September 2005 01:59, Paul Varner wrote: |
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> >>http://bugs.gentoo.org/show_bug.cgi?id=90680 |
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> >> |
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> >>Author: Paul Varner |
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> >> |
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> >>The current implementation of gentoolkit creates a portage.config |
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> >> object for every package object that it creates. While this is the |
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> >> correct thing to do from an object-oriented programming point of |
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> >> view, this implementation consumes an excessive amount of memory and |
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> >> CPU. The proposed patch changes the portage.config object for each |
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> >> package object to point to a single global object. |
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> >> |
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> >>If no one sees any serious issues with the patch, I will be placing |
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> >> it into gentoolkit. |
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> > |
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> > I tried doing this once before locally, but found some issue with it. |
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> > Unfortunately, I can't remember what that issue was. If you are |
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> > calling setcpv() for every call to the package object that utilizes |
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> > the config object and no utilizing packages (in gentoolkit or |
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> > otherwise) are utilizing threading, it should theoretically be okay. |
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> > Actually, I think it was the threading issue that delayed the fix. |
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> |
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> I can't remember the model for this, but there is some logic along the |
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> lines of intercepting config object writes with setattr and then |
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> cloning the config object. That way if the config is read-only only 1 |
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> is instantiated, but if you attempt to modify it, the config would |
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> clone itself, then proceed with the modification and return the cloned |
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> copy. Not sure how easy that would be to implement, perhaps some sort |
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> of wrapper class? |
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To share such an object the right way from an OO perspective would require |
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to pass the object along at package object instanciation. I doubt though |
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that the config object should be modified. But if it must in some cases a |
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lazy copy scheme is probably most efficient. You'd probably have the |
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editing code do something like: |
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this->editableConfig()->changeAttribute(...) |
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|
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Where the editableConfig function checks whether a copy has been made, if |
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so, it will just use that copy, else it will make a copy and return it. |
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|
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Paul |
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|
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-- |
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Paul de Vrieze |
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Gentoo Developer |
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Mail: pauldv@g.o |
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Homepage: http://www.devrieze.net |
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