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<DIV><FONT face=Arial size=2>Hi,</FONT></DIV>
<DIV><FONT face=Arial size=2> I get this error when i update a
netcdf file in independent mode.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> 2: MPI_File_write error =
Input/output error<BR> Unknow error occurs in writting
file</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Anyone have any idea what is going on ? This
happens when i scale up to 5 processors. </FONT></DIV>
<DIV><FONT face=Arial size=2> This sounds silly
but what happen is i use a root processor to keep track of which </FONT></DIV>
<DIV><FONT face=Arial size=2>position in the netcdf to append the new entry.
Whenever a processor wants to add an enrty</FONT></DIV>
<DIV><FONT face=Arial size=2>to the file, it sends a message to the root
processor. The root will return the latest position. </FONT></DIV>
<DIV><FONT face=Arial size=2>If there are five entries in the file, the root
processor will return 5. Therefore, the slave processor</FONT></DIV>
<DIV><FONT face=Arial size=2>will write the enrty at position six. The slave is
blocked before it get the message from the root</FONT></DIV>
<DIV><FONT face=Arial size=2>processor. Therefore, i don't see how does the I/O
error happens. Each processor should</FONT></DIV>
<DIV><FONT face=Arial size=2>be guarantee to write to different position in the
file.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thx</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
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