Hi,
  I am running into an issue with running applications in ALPHA_FS on more
than 32 cores.  The cores of index greater than or equal to 32 sit and spin,
as indicated by their uniformly small number of committed instructions,
during parallel sections of benchmarks with more than 32 threads.  The
problem exists in kernel v2.6.27, which we built using the method described
on the M5 site.
  I have done some testing, and I have identified that our kernels, v2.6.13
and v2.3.16, both schedule threads on all 64 cores.  Further, the file,
`.config.m5' contains a line to configure the maximum number of cores, which
is different for different linux versions:

  2.6.13, 2.6.16: CONFIG_NR_CPUS=64
  2.6.22, 2.6.27: CONFIG_NR_CPUS=32

  I've tried building a few different versions, and each asks "  Use M5 64
Processor Tsumani Modification (BIG_TSUNAMI) [Y/n/?]", but setting this
doesn't seem to have an affect on kernels 2.6.22 or 2.6.27.  The config
script restricts the CONFIG_NR_CPUS flag to 2-32 cores for kernel versions
2.6.22 and 2.6.26.
  Can someone give some insight into how to fix this so the v2.6.27
scheduler works with 64 cores?
  Thank you,
  Joel

-- 
 Joel Hestness
 PhD Student, Computer Architecture
 Dept. of Computer Science, University of Texas - Austin
 http://www.cs.utexas.edu/~hestness
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