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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Though it doesn’t fully exist yet, I have been
pondering writing a locking system built around memcached, and specifically the
add method. I wrote such a system for my own use the other night, would
like to generalize it a bit and would like to open source it. I would
also like to pattern it around something open sourced from work to allow for
locking over nfs, namely File::NFSLock<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><a
href="http://search.cpan.org/src/BBB/File-NFSLock-1.20/README">http://search.cpan.org/src/BBB/File-NFSLock-1.20/README</a><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Course, a locking system using memcached wouldn’t
really care about nfs, which is kind of the beauty. I would plan on mimicking
a few File::NFSLock functions, like returning a lock object that unlocks when
it leaves scope, blocking and non-blocking locks, blocking timeouts and stale
lock timeouts. Instead of locking on a file, one would lock on an
arbitrary word.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>In my tests going between two athlon 3200+s, I got around
10,000 add/delete cycles per second.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am not saying it would be a hard module to write, especially
since add does most of the work, but I think it could be quite useful. My
module from the other night, which by design, does some weird thing where only
one process per second gets the lock, has already solved a few problems for me.
It might also be that such a thing exists, but in my cpan searchings, I couldn’t
find anything.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>As a final note, whoever was responsible 1.1.12 and for
fixing the slow delete problem, many thanks. Just before I filed a bug
report, or at least emailed the list, I checked the changes and found what I
needed. Also wondering how to get version 1.1.12 into debian distributions.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Feedback welcome.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Earl<o:p></o:p></span></font></p>
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