[Openmp-commits] [PATCH] D21196: Excluded untied tasks from task stealing constraint

[Paul Osmialowski via Openmp-commits]

pawosm01 added a comment.

Runtime:

I'm using libomp from latest git master built using clang and gcc (tried both builds with the same result)

Benchmark:

strassen_taskdep from kastors-1.1 built using clang (it never catched livelock when built with gcc and having libomp as a GOMP drop-in replacement!)

Machine:

processor       : 31
vendor_id       : GenuineIntel
cpu family      : 6
model           : 45
model name      : Intel(R) Xeon(R) CPU E5-2690 0 @ 2.90GHz
stepping        : 7
microcode       : 0x710
cpu MHz         : 1200.000
cache size      : 20480 KB
physical id     : 1
siblings        : 16
core id         : 7
cpu cores       : 8
apicid          : 47
initial apicid  : 47
fpu             : yes
fpu_exception   : yes
cpuid level     : 13
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb xsaveopt pln pts dtherm tpr_shadow vnmi flexpriority ept vpid
bogomips        : 5787.09
clflush size    : 64
cache_alignment : 64
address sizes   : 46 bits physical, 48 bits virtual
power management:

System:

3.13.0-86-generic #131-Ubuntu SMP Thu May 12 23:33:13 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

Starting:

$ KMP_TOPOLOGY_METHOD=cpuinfo OMP_PROC_BIND=close OMP_DISPLAY_ENV=true OMP_STACKSIZE=64M OMP_NUM_THREADS=7 bin/strassen_taskdep -i 5 -n 4096 -d 5 -s 64

Successful run should print:

OPENMP DISPLAY ENVIRONMENT BEGIN

   _OPENMP='201511'
  [host] OMP_CANCELLATION='FALSE'
  [host] OMP_DEFAULT_DEVICE='0'
  [host] OMP_DISPLAY_ENV='TRUE'
  [host] OMP_DYNAMIC='FALSE'
  [host] OMP_MAX_ACTIVE_LEVELS='2147483647'
  [host] OMP_MAX_TASK_PRIORITY='0'
  [host] OMP_NESTED='FALSE'
  [host] OMP_NUM_THREADS='7'
  [host] OMP_PLACES='cores'
  [host] OMP_PROC_BIND='close'
  [host] OMP_SCHEDULE='static'
  [host] OMP_STACKSIZE='64M'
  [host] OMP_THREAD_LIMIT='2147483647'
  [host] OMP_WAIT_POLICY='PASSIVE'

OPENMP DISPLAY ENVIRONMENT END

Program : bin/strassen_taskdep
Size : 4096
Iterations : 5
Cutoff Size : 64
Cutoff depth : 5
Threads : 7
Time(sec):: avg : 5.616665 :: std : 0.431984 :: min : 5.050717 :: max : 6.352281 :: median : 5.648555


Repository:
  rL LLVM

https://reviews.llvm.org/D21196