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On Thursday 09 February 2006 01:17, Duncan wrote: |
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> Simon Stelling posted <43EA568D.6020307@g.o>, excerpted below, on |
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> My thinking, which is possibly incorrect (your input appreciated), is that |
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> file-based scripts get pulled into cache the first time they are executed, |
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> and will remain there (with a gig of memory) pretty much until I'm done |
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> doing my upgrades. At the same time, they are simply in cache, not |
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> something in bash's memory, so if the memory is needed, it will be |
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> reclaimed. As well, after I'm done and on to other tasks, the cached |
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> commands will eventually be replaced by other data, if need be. |
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> |
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> Aliases (and bash-functions) are held in memory. That's not as flexible |
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> as cache in terms of being knocked out of memory if the memory is needed |
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> by other things. Sure, that memory may be flushed to disk-based swap, but |
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> that's disk based the same as the actual script files I'm using, so |
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> reading it back into main memory if it's faulted out will take something |
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> comparable to the time it'd take to read in the script file again anyway. |
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> That's little gain, with the additional overhead and therefore loss of |
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> having to manage the temp-copy in swapped memory, if it comes to that. |
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Besides the fact that memory use is negligeable, you should keep into account |
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that scripts (even oneliners) use one memory page per script. Aliasses |
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however are stored by bash in a way that multiple aliases fit into one block |
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of memory. And when the memory is needed, bash will be bumped out of memory |
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too. But the idea is that those small aliasses will not actually need more |
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memory. |
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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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