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<p class="MsoNormal">All,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have a small gluster filesystem on 3 nodes.<o:p></o:p></p>
<p class="MsoNormal">I have a perl program that multi-threads and each thread writes it’s output to one of 3 files depending on some results.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My trouble is that I am seeing missing lines from the output.<o:p></o:p></p>
<p class="MsoNormal">The input is a file of 500 lines. Depending on the line, it would be written to one of three files, but when I total the lines put out, I am missing anywhere from 4 to 8 lines.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This is even the case if I use an input file that should all go to a single file.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">BUT… when I have it write to /tmp or /dev/shm, all of the lines expected are there.<o:p></o:p></p>
<p class="MsoNormal">This leads me to think there is something not happy with gluster and concurrent writes.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Here is the code for the actual write:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> flock(GOOD_FILES, LOCK_EX) or die $!;<o:p></o:p></p>
<p class="MsoNormal"> seek(GOOD_FILES, 0, SEEK_END) or die $!;<o:p></o:p></p>
<p class="MsoNormal"> print GOOD_FILES $lines_to_process[$tid-1] ."\n";<o:p></o:p></p>
<p class="MsoNormal"> flock(GOOD_FILES, LOCK_UN) or die $!;<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So I would expect the proper file locking is taking place.<o:p></o:p></p>
<p class="MsoNormal">Is it possible that gluster is not writing because of a race condition?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any insight as to where to look for a solution is appreciated.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Brian Andrus<o:p></o:p></p>
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