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<DIV><FONT face=Arial size=2>To All BCX User,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>the cluster BCX will be down for maintenance
Wednesday the 17th of September.</FONT></DIV>
<DIV><FONT face=Arial size=2>The maintenance operations will start at 8 a.m. and
will end in late afternoon.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>*** Four important change in the configuration
will be done: ***</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>1) /scratch space will be increased of
24Tbyte</FONT></DIV>
<DIV><FONT face=Arial size=2>(DATA already present on /scratch will NOT be
removed);</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>2) /scratch (GPFS) will be moved from
GigabitEthernet to InfiniBand network,</FONT></DIV>
<DIV><FONT face=Arial size=2>this should increase the row performance by a
factor of 10</FONT></DIV>
<DIV><FONT face=Arial size=2>(DATA already present on /scratch will NOT be
removed);</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>3) new more strict memory limits will be set, so
that applications trying</FONT></DIV>
<DIV><FONT face=Arial size=2>to allocate more than 90% of total virtual memory (
roughly 11Gbyte/node or 2.8Gbyte/core ) </FONT></DIV>
<DIV><FONT face=Arial size=2>will be </FONT><FONT face=Arial
size=2>killed before compute node hangs;</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>4) default stack limit will be set to 10Mbyte to
prevent shell applications (example tcl)</FONT></DIV>
<DIV><FONT face=Arial size=2>to use too much memory. If this limit is not
enought for your application, you are free</FONT></DIV>
<DIV><FONT face=Arial size=2>to change it inside your job script before the
application executable is run.</FONT></DIV>
<DIV><FONT face=Arial size=2>Example:</FONT></DIV>
<DIV><FONT face=Arial size=2>#!/bin/bash <BR>#BSUB -W 0:25<BR>#BSUB -a
openmpi<BR>#BSUB -n 30<BR></FONT><FONT face=Arial size=2>.
/prod/modules/tcl_3.2/init/bash</FONT></DIV>
<DIV><FONT face=Arial size=2>module load openmpi/1.2.5/intel</FONT></DIV>
<DIV><FONT face=Arial size=2>module load acml/3.6.0--intel--10.1</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>ulimit -s unlimited</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>mpirun.lsf my_application.x<BR></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>best regards,</FONT></DIV>
<DIV><FONT face=Arial size=2>Carlo Cavazzoni</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>for any question, doubt or request of
support</FONT></DIV>
<DIV><FONT face=Arial size=2>write to <A
href="mailto:superc@cineca.it">superc@cineca.it</A></FONT></DIV>
<DIV><FONT face=Arial size=2> </DIV></FONT></BODY></HTML>