David, Nathan Collier has kindly run a test on Titan, Satish on Mira and Hopper, and Victor on Ranger with a basic optimized build of PETSc (all C code) Please find below some configure and make timings from the latest PETSc master. The Titan times for both configure and make are unacceptable. For total build time Titan is 3.5 times slower than Mira and Hopper and at least 10 times slower than laptops. The "time" results on Titan are disturbing configure real 14m32.169s (since the user + sys time is much less than real time, what is it waiting on?) user 1m51.527s sys 3m40.734s make real 15m56.004s user 8m8.971s sys 52m42.734s (why so much?) which I read as either the filesystem or the compiler system (location of the compilers, license server of the compilers, ...) is really badly configured. The Hopper configure time with the default TMPDIR=/scratch/scratchdirs/balay is is unacceptable but if you actually use the real /tmp it becomes somewhat reasonable. Feel free to share this information with local experts, I suggest you view the below table in a fixed width font editor like Emacs or Vi so the columns line up. configure time make time Total compilers filesystem Titan 14m32s 15m56s 30m28s Intel 14 /lustre/atlas1/geo103/proj-shared/ 41m38s 9m5s 50m43s /ccs/home/ (no load on login node) 13m (no load on a different login node) Mira 6m59s 1m49s 8m48s IBM /gpfs/mira-home/ Hopper 23m17 1m45s 25m2s /global/u2/b/balay/petsc.clone default TMPDIR=/scratch/scratchdirs/balay 6m17s 1m39s 7m57s manually set TMPDIR=/tmp NSF Ranger UT Austin 5m10s 1m28s 6m38s default, whatever it is Linux laptop 53s 1m13s 2m6s Gnu compile and compiler local Apple laptop 1m14s 54s 2m8s clang compile and compiler local Linux workstation 1m11s 22s 1m33s Gnu compile and compiler local 1m37s 29s 2m6s Gnu compile directory local; compiler directory remote 3m11s 25s 3m36s Intel 13 compile directory local; compiler directory remote PETSc has about 1000 source files that need compiling The configure is essentially sequential, the make extremely parallel. During configure the source code is on the listed file system, all .o and executables are on /tmp During the make the source code and all .o are on the listed file system