Thanks Matt, I think I got it. Does that mean I need to configure a PETSC_ARCH as --with-debugging=0 so that I can used it later on.
best, Alan On , Matthew Knepley <knepley at gmail.com> wrote: > On Fri, Jun 3, 2011 at 3:38 PM, Barry Smith bsmith at mcs.anl.gov> wrote: > On Jun 3, 2011, at 3:30 PM, Matthew Knepley wrote: > > On Fri, Jun 3, 2011 at 3:28 PM, zhenglun.wei at gmail.com> wrote: > > Thanks for your reply. > > So, if I want to use '--with-debugging=0', what is the PETSC_ARCH equal > to? > > > > When you run configure, at the end it prints out a LARGE message that > indicates > > > > - What PETSC_ARCH it has chosen > > > > - Exactly the command line to run when building > > > > This information is also stored in configure.log > You should provide a value for the environmental variable PETSC_ARCH > before running ./configure > For example PETSC_ARCH=arch-debug ./configure --with-debugging=1 > otherstuff > then PETSC_ARCH=arch-opt ./configure --with-debugging=0 otherstuff > This is fragile since it depends on your shell. Just use > ./configure --with-debugging=0 --PETSC_ARCH=arch-opt > Matt > > > > Matt > > > > I just tried to use PETSC = arch-opt, and a error message comes up: > > ~/petsc-dev/conf/variables:95: > ~/petsc-dev/arch-opt/conf/petscvariables: No such file or directory > > ~l/petsc-dev/conf/rules:1018: ~/petsc-dev/arch-opt/conf/petscrules: No > such file or directory > > make: *** No rule to make target > `~l/petsc-dev/arch-opt/conf/petscrules'. Stop. > > this really confused me. > > > > thanks, > > Alan > > > > On , Barry Smith bsmith at mcs.anl.gov> wrote: > > > > > > > > > On Jun 3, 2011, at 2:57 PM, Alan Wei wrote: > > > > > > > > > > > > > Dear Sir/Madam, > > > > > > > Lately, I read there is a optimized version of PETSc by > using '--with-debugging=0'. I have two questions here: > > > > > > > 1, Do I need to use '/config/configure.py ... --with-debugging=0' > when I configure the PETSc in order to use the non-debugging version of > PETSc? Therefore, if I want to switch PETSc between these two versions, I > have to keep configuring. > > > > > > > > > > > > > > > > > > ABSOLUTELY NOT. You use two different values of the environmental > variable PETSC_ARCH and switch back and forth by changing the variable. > You can even change it on the make command line. For example make mycode > PETSC_ARCH=arch-opt > > > > > > > > > > > > Note that you can use any name you want for the values of PETSC_ARCH. > I often use arch-debug and arch-opt to keep track of them. > > > > > > > > > > > > > > > > > > > 2, I was using the '--with-debugging=0' to configure the PETSc. > However, I tested the computational rate by executing the ex29.c. The > non-debugging version does not improve the speed much; in the contrary, > it slow down the speed a little bit. The comparison is attached here. Any > idea on this. > > > > > > > > > > > > It depends on the compiler and particular code you are running. We > recommend using the option -log_summary to see how much time is spent in > each part of the computation and how much it gets better with > optimization. > > > > > > > > > > > > > > > > > > Barry > > > > > > > > > > > > > > > > > > > > > > > > > > thanks in advance, > > > > > > > Alan > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > What most experimenters take for granted before they begin their > experiments is infinitely more interesting than any results to which > their experiments lead. > > -- Norbert Wiener > -- > What most experimenters take for granted before they begin their > experiments is infinitely more interesting than any results to which > their experiments lead. > -- Norbert Wiener -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20110603/50a459c7/attachment.htm>
