---1480530994-1486697280-915726022=:4716
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Content-ID: <Pine.LNX.3.96.990107172805.4810B@Linuz.sns.it>
Here's my second attempt at creating an `official' linux-kernel patch ;)
Since I have an ancient 16Mb 486, I often look at ways to save memory.
One thing I noticed is that most of the kernel memory reported as `data'
at bootstrap, is used for an array of mem_map_t structures, that describes the
status, usage, and so on, of all the physical pages of memory.
Since it is a really big array (4096 elements on my 16Mb box), even a small
change in the struct size will have noticeable effect on kernel memory usage.
So I came out with this patch, which, despite being tiny,
saves 4kb for every 2Mb of physical RAM.
On my 16Mb box this means the kernel uses 32kb less memory,
and on a typical 64Mb Intel you save 128kb.
It is not exactly little, considering that the `init' memory added in 2.1
normally saves 20-40kb of memory.
The patch attached is for 2.2.0-pre4, but I couldn't test it yet, sorry.
I have tested the patch on 2.0.36 and 2.1.119, and it worked for me.
Bye,
Massimiliano Ghilardi
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| I have yet to meet a person who had a bad experience of Linux. |
| Most have never had an experience. |
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