Ok more information (had to build newer hwloc) My job today only 2 processes are running at half speed and they indeed are sharing the same core:
[root@nyx7000 ~]# for x in `cat /tmp/pids `; do echo -n "$x "; hwloc-bind --get-last-cpu-location --pid $x; done | sort -k 2 1164 0x00000001,0x0 1158 0x00000010,0x0 1165 0x00000010,0x0 1167 0x00000020 1157 0x00000200 1159 0x00000400 1160 0x00002000 1163 0x00004000 1166 0x00020000 1161 0x00040000 1168 0x00200000 1162 0x00400000 1157 brockp 20 0 1885m 1.8g 456 R 99.6 0.2 9:49.55 stream 1159 brockp 20 0 1885m 1.8g 456 R 99.6 0.2 8:10.91 stream 1161 brockp 20 0 1885m 1.8g 456 R 99.6 0.2 9:49.55 stream 1162 brockp 20 0 1885m 1.8g 456 R 99.6 0.2 9:49.54 stream 1163 brockp 20 0 1885m 1.8g 456 R 99.6 0.2 9:49.55 stream 1164 brockp 20 0 1885m 1.8g 456 R 99.6 0.2 9:49.53 stream 1160 brockp 20 0 1885m 1.8g 456 R 97.7 0.2 9:49.54 stream 1166 brockp 20 0 1885m 1.8g 456 R 97.7 0.2 9:49.53 stream 1167 brockp 20 0 1885m 1.8g 456 R 97.7 0.2 9:49.46 stream 1168 brockp 20 0 1885m 1.8g 456 R 97.7 0.2 8:10.86 stream 1158 brockp 20 0 1885m 1.8g 456 R 48.9 0.2 4:54.78 stream 1165 brockp 20 0 1885m 1.8g 456 R 48.9 0.2 4:54.76 stream This is very strange. Is there a way to ask hwloc to show me all processes that are using a given cpu? Brock Palen www.umich.edu/~brockp CAEN Advanced Computing bro...@umich.edu (734)936-1985 On Nov 2, 2012, at 4:30 PM, Brice Goglin wrote: > Le 02/11/2012 21:22, Brice Goglin a écrit : >> hwloc-bind --get-last-cpu-location --pid <pid> should give the same >> info but it seems broken on my machine right now, going to debug. > > Actually, that works fine once you try it on a non-multithreaded program > that uses all cores :) > > So you can use top or hwloc-bind --get-last-cpu-location --pid <pid> to > find out where each process runs. > > Brice > > _______________________________________________ > hwloc-users mailing list > hwloc-us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/hwloc-users