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<DIV><FONT size=2>Couple of points:</FONT></DIV>
<DIV><FONT size=2>1. Sticky bit is useless:</FONT></DIV>
<DIV><FONT size=2>Quote "man sticky":</FONT></DIV>
<DIV><FONT size=2>"A special file mode, called the sticky bit (mode S_ISVTX), is
used to<BR>indicate special treatment for directories. It is ignored for
regular files"</FONT></DIV>
<DIV><FONT size=2>2. </FONT><FONT size=3>Executable's copied to
swap</FONT></DIV>
<DIV><FONT size=2>This is not true for a number of modern OS's inc FreeBSD and
linux?</FONT></DIV>
<DIV><FONT size=2>The only one that springs to mind that still does this is Irix
but its been</FONT></DIV>
<DIV><FONT size=2>a while since I dug down into this behaviour on OS's other
than FreeBSD</FONT></DIV>
<DIV><FONT size=2>so I would be talking crap :P</FONT></DIV>
<DIV><FONT size=2>3. Might want to trim the crap from you posts i.e. the 220
lines at</FONT></DIV>
<DIV><FONT size=2>the bottom :)</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2> Steve / K</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV>----- Original Message ----- </DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=defilm@acm.org href="mailto:defilm@acm.org">Mark J. DeFilippis</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=cod@icculus.org
href="mailto:cod@icculus.org">cod@icculus.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> 09 December 2004 12:45</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [cod] Multiple COD:UO
servers on the same box</DIV>
<DIV><FONT size=2></FONT><BR></DIV><BR>You have been getting some excellent
advice and wonderful help.<BR>Was doing great, up until this part here.
(BTW, I also use screen,<BR>is it more reliable than nohup. nohup
protects against a Hangup signal<BR>(-15), and there are other signs you wish
to protect against. In addition,<BR>I have seen instances, depending on
execution scheduling, where the<BR>executable WILL receive a HUP signal if you
terminate the shell prior<BR>to it disassociating the controlling terminal
from the process. (See nohup(1))<BR>(In simpler terms, a nohup is simply
fork(2)s a child, turns off certain signal<BR>processing, and then
disassociates itself from your shell process, making its<BR>parent process
your shell's parent process which is often process 1 init.<BR><BR>With regards
to copying executables, or using the same code. PLEASE<BR>use the same
executable. You can use a hardlink if on the same filesystem,<BR>(otherwise a
ln will copy the file anyway), or symbolic. I recommend the
hard<BR>link. In addition, set the sticky bit on the
executable.<BR><BR>This will induce less lag, as the executable is, on
execution, copied to swap<BR>space only once for ALL instances, and not each
time it is spawned. In addition<BR>depending on the number of instances, there
is a memory savings.<BR><BR>Linux will share text pages, however your Heap and
Stack will be allocated in a<BR>separate memory segment. If a process
sharing an executable attempts to<BR>write said executable, a fork_on_write(2)
will be executed. (See vmstat(1))<BR>Thus, if a single process goes hog wild,
it will NOT impact readonly text (aka<BR>code) (other processes sharing the
same readonly text), at all.<BR><BR>This does not mean if you have a BUG in
the code, and one process hits<BR>it, and goes in to a spin loop it won't
impact your other processes. In fact,<BR>regardless of what you do, if you
have that type of bug, the result will be<BR>the same whether you are running
the same code or two executables.<BR><BR>Loading the text pages in to memory
once saves memory, and has NO<BR>negative impact at all. I spent much of
my early career writing kernel code<BR>so I know all too often how this
works. (Yes... Multi-threaded link libraries<BR>especially!)<BR><BR>But
take all the other good stuff people have been providing to you. They<BR>know
their stuff. (Scripts even! can't get better than that!!) Keep
them coming...<BR>I just grabbed another Dual P4 3.0, and am migrating off two
older single<BR>pents. I am lazy and given a stub of code.... heck, Ill use
it! ;-))<BR></BLOCKQUOTE><br>================================================<br>
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