Hi. > I use this occasion to propose something to the linux-smp world : when you > want to send a MPI message within a SMP node, almost all of the MPI > implementation use a shared memory area and do 2 copies (Memory space > Process 1 => Shared memory Area => Memory space Process 2). This design is > OK for small messages, the latency is good if you avoid the use of locks. > But for larege messages, the bandwith is limited to half of the memory > copy performance (2 copies) and the shared memory area used is large. > I have implemented a direct copy with linux using a kernel module to copy > the data from User space 1 to user space 2 in one copy. The bandwith > measured is 2 times the initial bandwith. > > It would be great that the linux kernel itself provides this function. Do > you think it's possible/impossible/usefull/useless ? > > Patrick GEOFFRAY > --- > Matra Systemes & Information - MS&I > Ecole Normale Superieure de Lyon - LIP > Universite Lyon I > http://lhpca.univ-lyon1.fr I was looking forward for replies from all u ppl qualified enough to comment on the above proposal. Me being a newbie to kernel hacking and wanting to explore the possibility of running a linux cluster with dual processors, I feel it is useful, but I really cannot comment on the possibility/impossibility/desireablity of including this in the Linux kernel. -Manoj e-mail : [EMAIL PROTECTED] fax : 0091-79-2864310 post : Manoj Warrier, Scientist SC, Institute for Plasma Research, BHAT, Gandhinagar, Gujrat, India - 382428 - Linux SMP list: FIRST see FAQ at http://www.irisa.fr/prive/dmentre/smp-howto/ To Unsubscribe: send "unsubscribe linux-smp" to [EMAIL PROTECTED]
