0.00/0.00 c Set FPU double precision.
0.89/0.92 c Parse Cnf success: #var: 370048 #clause: 1118066
0.89/0.92 c Find Units : 94
0.89/0.99 c Find Invs : 5
1.19/1.20 c Find Ands : 367704 AvgFaninNum: 2
1.19/1.22 c Find Xors : 0 AvgFaninNum: nan
1.19/1.25 c Find Ite : 0
1.49/1.54 c UnDirect variable: 0
1.49/1.54 c UnDirect to Direct Gate: 0
1.49/1.54 c Forced Direct Gate: 0 Unuse unDirect Gate: 0
1.49/1.59 c Break Cycle : 0
1.49/1.59 c Total Root : 1833 Undef Var: 2344
1.79/1.83 c After covering, Total Root: 1833 Leaf: 2344
1.79/1.83 c Variable( cover/uncovered/unused ): 370048 0 0
1.79/1.83 c Unit Clauses: 94
1.79/1.83 c Binary Clauses( cover/uncovered ): 735408 7391
1.79/1.83 c Clauses( cover/uncovered ): 367704 7467
1.79/1.83 c Total Clauses( cover/uncovered ): 1103206 14858 98.6711%
1.79/1.83 c Covered Ands: 367704 Invs: 0 Xors: 0 Ites: 0
1.89/1.99 c Uncover Clauses avg size: 22.6289 max size: 493
1.99/2.00 c Final circuit: i/l/o/s 2344 0 14753 463423
1.99/2.00 c CnfToAig: Time: 1.99 s
3.58/3.61 c TmMap: Set choices finish.
3.68/3.78 c TmMap: Set big and: 60346
3.68/3.78 c TmMap: Origin: 465768 ClauseNum: 1390269 --> New: 122312 ClauseNum: 668803
3.68/3.78 c TmMap: Time: 0.33
6.19/6.21 c Simulation --> TransNum: 371395/668803 Try to Add: #clause: 119353 #xorclause: 5712
6.29/6.33 c #var: 85206 #clauses: 148396 Solving...
15.08/15.11 c Abstract SAT
15.48/15.50 c Simulation --> TransNum: 490598/668803 Try to Add: #clause: 6307 #xorclause: 0
15.48/15.51 c #var: 87685 #clauses: 125237 Solving...
16.89/16.90 c Abstract SAT
17.19/17.29 c Simulation --> TransNum: 505976/668803 Try to Add: #clause: 3418 #xorclause: 763
17.29/17.30 c #var: 89989 #clauses: 130085 Solving...
17.69/17.71 c Abstract SAT
17.69/17.71 c Simulation --> TransNum: 668803/668803 Try to Add: #clause: 133391 #xorclause: 2341
17.69/17.76 c #var: 107544 #clauses: 197648 Solving...
18.79/18.82 s UNSATISFIABLE
18.79/18.83 c CPU time: 18.83 s
runsolver Copyright (C) 2010-2011 Olivier ROUSSEL
This is runsolver version 3.3.0 (svn: 935)
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
command line: BIN/runsolver --timestamp -w /tmp/evaluation-result-3293809-1303790155/watcher-3293809-1303790155 -o /tmp/evaluation-result-3293809-1303790155/solver-3293809-1303790155 -C 2400 -W 1300 -M 7680 qutersat_release HOME/instance-3293809-1303790155.cnf 1798267007
running on 2 cores: 4,6
Enforcing CPUTime limit (soft limit, will send SIGTERM then SIGKILL): 2400 seconds
Enforcing CPUTime limit (hard limit, will send SIGXCPU): 2430 seconds
Enforcing wall clock limit (soft limit, will send SIGTERM then SIGKILL): 1300 seconds
Enforcing VSIZE limit (soft limit, will send SIGTERM then SIGKILL): 7864320 KiB
Enforcing VSIZE limit (hard limit, stack expansion will fail with SIGSEGV, brk() and mmap() will return ENOMEM): 7915520 KiB
Current StackSize limit: 10240 KiB
[startup+0 s]
/proc/loadavg: 4.16 3.96 3.59 5/189 13907
/proc/meminfo: memFree=21910912/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=41040 CPUtime=0 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 2127 0 0 0 0 0 0 0 23 0 1 0 569246033 42024960 2061 33554432000 4194304 6016207 140734173853104 18446744073709551615 4272580 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 10260 2074 372 445 0 3804 0
[startup+0.0186989 s]
/proc/loadavg: 4.16 3.96 3.59 5/189 13907
/proc/meminfo: memFree=21910912/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=42064 CPUtime=0.01 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 4214 0 0 0 1 0 0 0 23 0 1 0 569246033 43073536 4148 33554432000 4194304 6016207 140734173853104 18446744073709551615 4804539 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 10516 4148 379 445 0 4060 0
Current children cumulated CPU time (s) 0.01
Current children cumulated vsize (KiB) 42064
[startup+0.100713 s]
/proc/loadavg: 4.16 3.96 3.59 5/189 13907
/proc/meminfo: memFree=21910912/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=57424 CPUtime=0.08 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 7890 0 0 0 8 0 0 0 23 0 1 0 569246033 58802176 7824 33554432000 4194304 6016207 140734173853104 18446744073709551615 4779602 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 14356 7826 379 445 0 7900 0
Current children cumulated CPU time (s) 0.08
Current children cumulated vsize (KiB) 57424
[startup+0.300674 s]
/proc/loadavg: 4.16 3.96 3.59 5/189 13907
/proc/meminfo: memFree=21910912/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=93520 CPUtime=0.29 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 16995 0 0 0 28 1 0 0 24 0 1 0 569246033 95764480 16929 33554432000 4194304 6016207 140734173853104 18446744073709551615 4309874 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 23380 16929 379 445 0 16924 0
Current children cumulated CPU time (s) 0.29
Current children cumulated vsize (KiB) 93520
[startup+0.700606 s]
/proc/loadavg: 4.16 3.96 3.59 5/189 13907
/proc/meminfo: memFree=21910912/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=146512 CPUtime=0.69 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 30231 0 0 0 66 3 0 0 25 0 1 0 569246033 150028288 30165 33554432000 4194304 6016207 140734173853104 18446744073709551615 4279516 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 36628 30165 379 445 0 30172 0
Current children cumulated CPU time (s) 0.69
Current children cumulated vsize (KiB) 146512
[startup+1.50046 s]
/proc/loadavg: 4.16 3.96 3.59 5/190 13908
/proc/meminfo: memFree=21672576/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=199120 CPUtime=1.49 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 41757 0 0 0 144 5 0 0 25 0 1 0 569246033 203898880 41691 33554432000 4194304 6016207 140734173853104 18446744073709551615 4297197 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 49780 41691 398 445 0 43324 0
Current children cumulated CPU time (s) 1.49
Current children cumulated vsize (KiB) 199120
[startup+3.10116 s]
/proc/loadavg: 4.16 3.96 3.59 5/190 13908
/proc/meminfo: memFree=21665136/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=246992 CPUtime=3.09 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 55691 0 0 0 303 6 0 0 25 0 1 0 569246033 252919808 55625 33554432000 4194304 6016207 140734173853104 18446744073709551615 4779602 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 61748 55627 670 445 0 55292 0
Current children cumulated CPU time (s) 3.09
Current children cumulated vsize (KiB) 246992
[startup+6.30056 s]
/proc/loadavg: 4.15 3.97 3.60 5/190 13909
/proc/meminfo: memFree=21508408/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=317928 CPUtime=6.29 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 73611 0 0 0 621 8 0 0 25 0 1 0 569246033 325558272 73545 33554432000 4194304 6016207 140734173853104 18446744073709551615 4752737 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 79482 73545 694 445 0 73026 0
Current children cumulated CPU time (s) 6.29
Current children cumulated vsize (KiB) 317928
[startup+12.7003 s]
/proc/loadavg: 4.13 3.97 3.60 5/190 13909
/proc/meminfo: memFree=20966760/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=317928 CPUtime=12.69 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 73620 0 0 0 1261 8 0 0 25 0 1 0 569246033 325558272 73554 33554432000 4194304 6016207 140734173853104 18446744073709551615 4424125 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 79482 73554 703 445 0 73026 0
Current children cumulated CPU time (s) 12.69
Current children cumulated vsize (KiB) 317928
Solver just ended. Dumping a history of the last processes samples
[startup+15.9008 s]
/proc/loadavg: 4.12 3.97 3.60 5/190 13909
/proc/meminfo: memFree=20550668/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=347844 CPUtime=15.88 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 80265 0 0 0 1580 8 0 0 25 0 1 0 569246033 356192256 80187 33554432000 4194304 6016207 140734173853104 18446744073709551615 4425075 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 86961 80187 721 445 0 80505 0
Current children cumulated CPU time (s) 15.88
Current children cumulated vsize (KiB) 347844
[startup+17.5005 s]
/proc/loadavg: 4.12 3.97 3.60 5/190 13909
/proc/meminfo: memFree=20495920/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=351088 CPUtime=17.5 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 81451 0 0 0 1741 9 0 0 25 0 1 0 569246033 359514112 81364 33554432000 4194304 6016207 140734173853104 18446744073709551615 4424223 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 87772 81364 721 445 0 81316 0
Current children cumulated CPU time (s) 17.5
Current children cumulated vsize (KiB) 351088
[startup+18.3003 s]
/proc/loadavg: 4.12 3.97 3.60 5/190 13909
/proc/meminfo: memFree=20495920/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=387660 CPUtime=18.29 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 83203 0 0 0 1820 9 0 0 25 0 1 0 569246033 396963840 83073 33554432000 4194304 6016207 140734173853104 18446744073709551615 4733382 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 96915 83073 721 445 0 90459 0
Current children cumulated CPU time (s) 18.29
Current children cumulated vsize (KiB) 387660
[startup+18.7072 s]
/proc/loadavg: 4.12 3.97 3.60 5/190 13909
/proc/meminfo: memFree=20472608/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=387660 CPUtime=18.7 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 83203 0 0 0 1861 9 0 0 25 0 1 0 569246033 396963840 83073 33554432000 4194304 6016207 140734173853104 18446744073709551615 4425132 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 96915 83073 721 445 0 90459 0
Current children cumulated CPU time (s) 18.7
Current children cumulated vsize (KiB) 387660
[startup+18.8012 s]
/proc/loadavg: 4.12 3.97 3.60 5/190 13909
/proc/meminfo: memFree=20472608/32951124 swapFree=67111348/67111528
[pid=13907] ppid=13905 vsize=387660 CPUtime=18.79 cores=4,6
/proc/13907/stat : 13907 (qutersat_releas) R 13905 13907 12511 0 -1 4202496 83203 0 0 0 1870 9 0 0 25 0 1 0 569246033 396963840 83073 33554432000 4194304 6016207 140734173853104 18446744073709551615 4791770 0 0 4096 16386 0 0 0 17 4 0 0 0
/proc/13907/statm: 96915 83073 721 445 0 90459 0
Current children cumulated CPU time (s) 18.79
Current children cumulated vsize (KiB) 387660
Child status: 0
Real time (s): 18.8505
CPU time (s): 18.8491
CPU user time (s): 18.7412
CPU system time (s): 0.107983
CPU usage (%): 99.9929
Max. virtual memory (cumulated for all children) (KiB): 387660
getrusage(RUSAGE_CHILDREN,...) data:
user time used= 18.7412
system time used= 0.107983
maximum resident set size= 0
integral shared memory size= 0
integral unshared data size= 0
integral unshared stack size= 0
page reclaims= 83208
page faults= 0
swaps= 0
block input operations= 0
block output operations= 0
messages sent= 0
messages received= 0
signals received= 0
voluntary context switches= 11
involuntary context switches= 25
runsolver used 0.030995 second user time and 0.079987 second system time
The end
Begin job on node111 at 2011-04-26 05:55:56
IDJOB=3293809
IDBENCH=88178
IDSOLVER=1607
FILE ID=node111/3293809-1303790155
RUNJOBID= node111-1303789524-13420
PBS_JOBID= 13157239
Free space on /tmp= 70744 MiB
SOLVER NAME= QuteRSat 2011-03-01
BENCH NAME= SAT-Race-2010-CNF/software-verification/nec/hard-6-U-7061.cnf
COMMAND LINE= qutersat_release BENCHNAME RANDOMSEED
RUNSOLVER COMMAND LINE= BIN/runsolver --timestamp -w /tmp/evaluation-result-3293809-1303790155/watcher-3293809-1303790155 -o /tmp/evaluation-result-3293809-1303790155/solver-3293809-1303790155 -C 2400 -W 1300 -M 7680 qutersat_release HOME/instance-3293809-1303790155.cnf 1798267007
TIME LIMIT= 2400 seconds
MEMORY LIMIT= 7680 MiB
NBCORE= 2
MD5SUM BENCH= b15321a24257fa4bdfd9c20c782f4c0e
RANDOM SEED=1798267007
node111.alineos.net Linux 2.6.18-164.el5 #1 SMP Thu Sep 3 03:28:30 EDT 2009
/proc/cpuinfo:
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 26
model name : Intel(R) Xeon(R) CPU X5550 @ 2.67GHz
stepping : 5
cpu MHz : 2666.849
cache size : 8192 KB
physical id : 0
siblings : 4
core id : 0
cpu cores : 4
apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 11
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 syscall nx rdtscp lm constant_tsc ida nonstop_tsc pni monitor ds_cpl vmx est tm2 cx16 xtpr popcnt lahf_lm
bogomips : 5333.69
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: [8]
processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 26
model name : Intel(R) Xeon(R) CPU X5550 @ 2.67GHz
stepping : 5
cpu MHz : 2666.849
cache size : 8192 KB
physical id : 1
siblings : 4
core id : 0
cpu cores : 4
apicid : 16
fpu : yes
fpu_exception : yes
cpuid level : 11
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 syscall nx rdtscp lm constant_tsc ida nonstop_tsc pni monitor ds_cpl vmx est tm2 cx16 xtpr popcnt lahf_lm
bogomips : 5428.12
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: [8]
processor : 2
vendor_id : GenuineIntel
cpu family : 6
model : 26
model name : Intel(R) Xeon(R) CPU X5550 @ 2.67GHz
stepping : 5
cpu MHz : 2666.849
cache size : 8192 KB
physical id : 0
siblings : 4
core id : 1
cpu cores : 4
apicid : 2
fpu : yes
fpu_exception : yes
cpuid level : 11
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 syscall nx rdtscp lm constant_tsc ida nonstop_tsc pni monitor ds_cpl vmx est tm2 cx16 xtpr popcnt lahf_lm
bogomips : 5332.75
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: [8]
processor : 3
vendor_id : GenuineIntel
cpu family : 6
model : 26
model name : Intel(R) Xeon(R) CPU X5550 @ 2.67GHz
stepping : 5
cpu MHz : 2666.849
cache size : 8192 KB
physical id : 1
siblings : 4
core id : 1
cpu cores : 4
apicid : 18
fpu : yes
fpu_exception : yes
cpuid level : 11
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 syscall nx rdtscp lm constant_tsc ida nonstop_tsc pni monitor ds_cpl vmx est tm2 cx16 xtpr popcnt lahf_lm
bogomips : 5332.86
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: [8]
processor : 4
vendor_id : GenuineIntel
cpu family : 6
model : 26
model name : Intel(R) Xeon(R) CPU X5550 @ 2.67GHz
stepping : 5
cpu MHz : 2666.849
cache size : 8192 KB
physical id : 0
siblings : 4
core id : 2
cpu cores : 4
apicid : 4
fpu : yes
fpu_exception : yes
cpuid level : 11
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 syscall nx rdtscp lm constant_tsc ida nonstop_tsc pni monitor ds_cpl vmx est tm2 cx16 xtpr popcnt lahf_lm
bogomips : 5332.75
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: [8]
processor : 5
vendor_id : GenuineIntel
cpu family : 6
model : 26
model name : Intel(R) Xeon(R) CPU X5550 @ 2.67GHz
stepping : 5
cpu MHz : 2666.849
cache size : 8192 KB
physical id : 1
siblings : 4
core id : 2
cpu cores : 4
apicid : 20
fpu : yes
fpu_exception : yes
cpuid level : 11
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 syscall nx rdtscp lm constant_tsc ida nonstop_tsc pni monitor ds_cpl vmx est tm2 cx16 xtpr popcnt lahf_lm
bogomips : 5332.83
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: [8]
processor : 6
vendor_id : GenuineIntel
cpu family : 6
model : 26
model name : Intel(R) Xeon(R) CPU X5550 @ 2.67GHz
stepping : 5
cpu MHz : 2666.849
cache size : 8192 KB
physical id : 0
siblings : 4
core id : 3
cpu cores : 4
apicid : 6
fpu : yes
fpu_exception : yes
cpuid level : 11
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 syscall nx rdtscp lm constant_tsc ida nonstop_tsc pni monitor ds_cpl vmx est tm2 cx16 xtpr popcnt lahf_lm
bogomips : 5332.67
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: [8]
processor : 7
vendor_id : GenuineIntel
cpu family : 6
model : 26
model name : Intel(R) Xeon(R) CPU X5550 @ 2.67GHz
stepping : 5
cpu MHz : 2666.849
cache size : 8192 KB
physical id : 1
siblings : 4
core id : 3
cpu cores : 4
apicid : 22
fpu : yes
fpu_exception : yes
cpuid level : 11
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 syscall nx rdtscp lm constant_tsc ida nonstop_tsc pni monitor ds_cpl vmx est tm2 cx16 xtpr popcnt lahf_lm
bogomips : 5332.83
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: [8]
/proc/meminfo:
MemTotal: 32951124 kB
MemFree: 21910936 kB
Buffers: 1243356 kB
Cached: 7652092 kB
SwapCached: 132 kB
Active: 4650244 kB
Inactive: 5908244 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 32951124 kB
LowFree: 21910936 kB
SwapTotal: 67111528 kB
SwapFree: 67111348 kB
Dirty: 224624 kB
Writeback: 0 kB
AnonPages: 1662712 kB
Mapped: 18828 kB
Slab: 413556 kB
PageTables: 8312 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
CommitLimit: 83587088 kB
Committed_AS: 1943916 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 296008 kB
VmallocChunk: 34359440975 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
Hugepagesize: 2048 kB
Free space on /tmp at the end= 70744 MiB
End job on node111 at 2011-04-26 05:56:15