Hello,<br><br>My question is about virtual memory allocated by an open-mpi program. I am not familiar with memory managment and I will be grateful if you could explain me what I am observing when I launch my openMpi program on several machines.<br>

<br>My program is started on a server machine which comunicate with 72 client machines.<br>When I am doing a &quot;top&quot; on the Linux shell of the server machine: I can observe:<br><br>Mem:   2074468k total,     777848k used,      1296628k free,          4224k buffers<br>

Swap:  4192924k total,               52k used,      4192872k free,     339184k cached<br>PID       USER      PR  NI   VIRT       RES       SHR    S       %CPU    %MEM     TIME+        COMMAND<br>28211  realtime  20   0     <b>2104m</b>    158m     29m    S        100         4.6             1:04.14       MyOpenMPIProgram<br>

<br>What I do not understand is where the value of 2104m for the virtual memory comes from.<br>When I add the value of Mem used (777848k) to the value of the cache (339184k) : the amount is by far inferior to the Virtual memory (2104m).<br>

Are here part of the memory allocated by the clients taken into account ?<br>
Where are physically allocated these 2104m of data ?<br>I was assuming that a process cannot allocate more the 2Go of RAM on a 32bit machine, this would meant that part of this 2104m is located on the disk or anywhere else...<br>
<br>My configuration is:<br>OpenMPI 1.4 on Mandriva 2008 (32bit)<br>Program is started using: mpirun --mca btl_tcp_eager_limit 50000000 -v -machinefile machinefile.txt MyOpenMPIProgram<br>
<br>Thanks in advance for any help/tips (and sorry if this is not completly related to openmpi).<br><br>Olivier<br>