Subject: Kernel tuning & mmap
To: None <tech-embed@NetBSD.ORG>
From: Kyle Unice <kyle@midnighttech.com>
List: tech-embed
Date: 07/24/2002 14:27:09
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A couple of questions:
1. We need to strip down the RAM needs of the NetBSD kernel. Our
current kernel is 1.3Meg with about 1 Meg of data space. We have 8 Megs
on the board we are porting to. We changed MAXUSERS to 1 and IOBUFS to
5% of total ram. Does anyone have any other suggestions for reducing
the footprint of NetBSD on an embedded system?
2. We are using mmap to manage some device buffers and have questions as
to what the caching is for mmap buffers? If caching is turned on, then
we should be flushing our writes before expecting a state change. If it
is off, we should be ok.
Thanks
Kyle Unice
email: kyle@midnighttech.com
voice:801-572-0928
FAX:801-572-0478
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<p class=3DMsoNormal><font size=3D2 color=3Dblue face=3D"Comic Sans =
MS"><span
style=3D'font-size:10.0pt;font-family:"Comic Sans MS";color:blue'>A =
couple of
questions:</span></font></p>
<p class=3DMsoNormal><font size=3D2 color=3Dblue face=3D"Comic Sans =
MS"><span
style=3D'font-size:10.0pt;font-family:"Comic Sans MS";color:blue'>1. We =
need to
strip down the RAM needs of the NetBSD kernel. Our current kernel =
is
1.3Meg with about 1 Meg of data space. We have 8 Megs on the board =
we are
porting to. We changed MAXUSERS to 1 and IOBUFS to 5% of total =
ram.
Does anyone have any other suggestions for reducing the footprint of =
NetBSD on
an embedded system?</span></font></p>
<p class=3DMsoNormal><font size=3D2 color=3Dblue face=3D"Comic Sans =
MS"><span
style=3D'font-size:10.0pt;font-family:"Comic Sans =
MS";color:blue'> </span></font></p>
<p class=3DMsoNormal><font size=3D2 color=3Dblue face=3D"Comic Sans =
MS"><span
style=3D'font-size:10.0pt;font-family:"Comic Sans MS";color:blue'>2. We =
are using
mmap to manage some device buffers and have questions as to what the =
caching is
for mmap buffers? If caching is turned on, then we should be =
flushing our
writes before expecting a state change. If it is off, we should be =
ok.</span></font></p>
<p class=3DMsoNormal><font size=3D2 color=3Dblue face=3D"Comic Sans =
MS"><span
style=3D'font-size:10.0pt;font-family:"Comic Sans =
MS";color:blue'> </span></font></p>
<p class=3DMsoNormal><font size=3D2 color=3Dblue face=3D"Comic Sans =
MS"><span
style=3D'font-size:10.0pt;font-family:"Comic Sans =
MS";color:blue'>Thanks</span></font></p>
<p class=3DMsoNormal><font size=3D2 color=3Dblue face=3D"Comic Sans =
MS"><span
style=3D'font-size:10.0pt;font-family:"Comic Sans =
MS";color:blue'> </span></font></p>
<p class=3DMsoAutoSig><i><font size=3D4 color=3Dblue face=3D"MS =
Mincho"><span
style=3D'font-size:14.0pt;font-family:"MS =
Mincho";color:blue;font-style:italic'>Kyle
Unice</span></font></i></p>
<p class=3DMsoAutoSig><font size=3D2 color=3Dblue face=3D"MS =
Mincho"><span
style=3D'font-size:10.0pt;font-family:"MS Mincho";color:blue'>email:
kyle@midnighttech.com</span></font></p>
<p class=3DMsoAutoSig><font size=3D2 color=3Dblue face=3D"MS =
Mincho"><span
style=3D'font-size:10.0pt;font-family:"MS =
Mincho";color:blue'>voice:801-572-0928</span></font></p>
<p class=3DMsoAutoSig><font size=3D2 color=3Dblue face=3D"MS =
Mincho"><span
style=3D'font-size:10.0pt;font-family:"MS =
Mincho";color:blue'>FAX:801-572-0478</span></font></p>
<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'> </span></font></p>
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