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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Hi,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>I have a couple of questions regarding
Erlang CPU/memory Optimization.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<ol style='margin-top:0in' start=1 type=1>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>Due
to the single assignment restriction in Erlang, when changing values in a
record as below.<o:p></o:p></span></font></li>
</ol>
<p class=MsoNormal style='margin-left:1.0in'><font size=2 color=navy
face=Arial><span style='font-size:10.0pt;font-family:Arial;color:navy'>Eg: NewRecord
= OldRecord#record_type{attribute = Value}.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'> does
Erlang take a full copy of the record to change only the attribute called “attribute”?
If so, isn’t that a waste of full memory copying to just change one
attribute and if the old copy is never used?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<ol style='margin-top:0in' start=2 type=1>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>In
gen_server handle_call/handle_cast/etc, does the State parameter makes a
new copy in each call/cast/etc? Or changes the same State?<o:p></o:p></span></font></li>
</ol>
<p class=MsoNormal style='margin-left:.25in'><font size=2 color=navy
face=Arial><span style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<ol style='margin-top:0in' start=3 type=1>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>When
passing large lists/binary/etc to a function, are they going as references
or values (a full copy of data)?<o:p></o:p></span></font></li>
</ol>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<ol style='margin-top:0in' start=4 type=1>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>Is
there any overhead difference between writing functions in the form of, fun(A,
B, C) or fun([A,B,C]) or fun({A,B,B})?<o:p></o:p></span></font></li>
</ol>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<ol style='margin-top:0in' start=5 type=1>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>Is
there any overhead difference between if and case expressions?<o:p></o:p></span></font></li>
</ol>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<ol style='margin-top:0in' start=6 type=1>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>Is
it Ober or jInterface better to write Java based GUIs for Erlang Backends?
Any other better language for this? GS doesn’t have much support in
designing good interfaces.<o:p></o:p></span></font></li>
</ol>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<ol style='margin-top:0in' start=7 type=1>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>In
a high capacity system, is it better to run the Mnesia DB in the same
Erlang instance (no data transfer between processes) or have it as a RDBMS
in a separate Erlang instance, so that in a multi-CPU environment can
gives a higher capacity?<o:p></o:p></span></font></li>
</ol>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<ol style='margin-top:0in' start=8 type=1>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>Does
Mnesia bag type database does an exhaustive search when called
mnesia_match_object/3?<o:p></o:p></span></font></li>
</ol>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Thanks,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>- Eranga<o:p></o:p></span></font></p>
<p class=MsoNormal style='margin-left:.25in'><font size=2 color=navy
face=Arial><span style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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