Yes, you are right that the Inactive memory is stated as being utilizable by other applications. I had misread that part of the documentation.
Nonetheless, utilizing my hack has pretty much solved the problems I was seeing under Lion concerning slowness, heat, and the fan. In other words, when "purge" is periodically invoked to release Inactive memory, my computer runs faster, cooler, and with hardly any use of the fan. And by "faster", I also include faster shutdowns
Furthermore, I can cause those problems to return simply by disabling my hack. In other words, when I turn off my hack without changing anything else, the heat, fan, and slowness issues return. And by "slowness", I also include slow shutdowns.
And then, when I re-enable my hack, the heat, fan, and slowness issues more or less go away again ... and the computer shuts down noticeably faster again.
I have just finished performing those tests again, and the results continue to confirm what I have just now stated here.
The only thing that my hack affects is the amount of Inactive memory. Therefore, I have empircally demonstrated -- at least on my own computer -- that a large amount of Inactive memory has a negative noticeable effect on speed (including shutdown speed), temperature, and fan use, and that releasing this Inactive memory improves all of these items.
Why don't you just try this, yourself, and see whether you get these same, empirical results?
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