runsolver Copyright (C) 2010-2011 Olivier ROUSSEL
This is runsolver version 3.3.0 (svn: 977)
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-3468552-1307071637/watcher-3468552-1307071637 -o /tmp/evaluation-result-3468552-1307071637/solver-3468552-1307071637 -C 1800 -W 1900 -M 15500 HOME/clasp HOME/instance-3468552-1307071637.opb --berk-max=512 --berk-once --otfs=1 --recursive-str --dinit=1500,10000 --dsched=10000,1.1,20000 --restart-on-model --opt-heu=2
running on 4 cores: 0,2,4,6
Enforcing CPUTime limit (soft limit, will send SIGTERM then SIGKILL): 1800 seconds
Enforcing CPUTime limit (hard limit, will send SIGXCPU): 1830 seconds
Enforcing wall clock limit (soft limit, will send SIGTERM then SIGKILL): 1900 seconds
Enforcing VSIZE limit (soft limit, will send SIGTERM then SIGKILL): 15872000 KiB
Enforcing VSIZE limit (hard limit, stack expansion will fail with SIGSEGV, brk() and mmap() will return ENOMEM): 15923200 KiB
Current StackSize limit: 10240 KiB
[startup+0 s]
/proc/loadavg: 1.92 1.99 1.93 2/572 18917
/proc/meminfo: memFree=31967900/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=12708 CPUtime=0.01 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 580 0 0 0 1 0 0 0 25 0 1 0 818762537 13012992 517 33554432000 4194304 4933572 140735533045760 18446744073709551615 4719099 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 3177 517 374 181 0 186 0
[startup+0.0862319 s]
/proc/loadavg: 1.92 1.99 1.93 2/572 18917
/proc/meminfo: memFree=31967900/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=13116 CPUtime=0.08 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 678 0 0 0 8 0 0 0 25 0 1 0 818762537 13430784 615 33554432000 4194304 4933572 140735533045760 18446744073709551615 4319413 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 3279 615 374 181 0 288 0
Current children cumulated CPU time (s) 0.08
Current children cumulated vsize (KiB) 13116
[startup+0.100229 s]
/proc/loadavg: 1.92 1.99 1.93 2/572 18917
/proc/meminfo: memFree=31967900/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=13116 CPUtime=0.09 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 696 0 0 0 9 0 0 0 25 0 1 0 818762537 13430784 633 33554432000 4194304 4933572 140735533045760 18446744073709551615 4330162 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 3279 633 374 181 0 288 0
Current children cumulated CPU time (s) 0.09
Current children cumulated vsize (KiB) 13116
[startup+0.300148 s]
/proc/loadavg: 1.92 1.99 1.93 2/572 18917
/proc/meminfo: memFree=31967900/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=13512 CPUtime=0.29 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 775 0 0 0 29 0 0 0 25 0 1 0 818762537 13836288 712 33554432000 4194304 4933572 140735533045760 18446744073709551615 4718458 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 3378 712 374 181 0 387 0
Current children cumulated CPU time (s) 0.29
Current children cumulated vsize (KiB) 13512
[startup+0.70108 s]
/proc/loadavg: 1.92 1.99 1.93 2/572 18917
/proc/meminfo: memFree=31967900/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=14040 CPUtime=0.7 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 933 0 0 0 70 0 0 0 25 0 1 0 818762537 14376960 870 33554432000 4194304 4933572 140735533045760 18446744073709551615 4637163 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 3510 870 374 181 0 519 0
Current children cumulated CPU time (s) 0.7
Current children cumulated vsize (KiB) 14040
[startup+1.50087 s]
/proc/loadavg: 1.92 1.99 1.93 3/573 18918
/proc/meminfo: memFree=31964428/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=14968 CPUtime=1.49 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1145 0 0 0 149 0 0 0 25 0 1 0 818762537 15327232 1082 33554432000 4194304 4933572 140735533045760 18446744073709551615 4649364 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 3742 1082 374 181 0 751 0
Current children cumulated CPU time (s) 1.49
Current children cumulated vsize (KiB) 14968
[startup+3.10063 s]
/proc/loadavg: 1.92 1.99 1.93 3/573 18918
/proc/meminfo: memFree=31962196/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=15764 CPUtime=3.09 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1349 0 0 0 309 0 0 0 25 0 1 0 818762537 16142336 1286 33554432000 4194304 4933572 140735533045760 18446744073709551615 4717516 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 3941 1286 374 181 0 950 0
Current children cumulated CPU time (s) 3.09
Current children cumulated vsize (KiB) 15764
[startup+6.30112 s]
/proc/loadavg: 1.93 1.99 1.93 3/573 18918
/proc/meminfo: memFree=31961300/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=16160 CPUtime=6.3 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1452 0 0 0 630 0 0 0 25 0 1 0 818762537 16547840 1389 33554432000 4194304 4933572 140735533045760 18446744073709551615 4637201 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 4040 1389 374 181 0 1049 0
Current children cumulated CPU time (s) 6.3
Current children cumulated vsize (KiB) 16160
[startup+12.7009 s]
/proc/loadavg: 1.93 1.99 1.93 3/573 18918
/proc/meminfo: memFree=31960088/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=16708 CPUtime=12.7 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1571 0 0 0 1270 0 0 0 25 0 1 0 818762537 17108992 1508 33554432000 4194304 4933572 140735533045760 18446744073709551615 4319365 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 4177 1508 374 181 0 1186 0
Current children cumulated CPU time (s) 12.7
Current children cumulated vsize (KiB) 16708
[startup+25.5007 s]
/proc/loadavg: 1.95 1.99 1.93 3/573 18919
/proc/meminfo: memFree=31959440/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=17576 CPUtime=25.5 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1804 0 0 0 2550 0 0 0 25 0 1 0 818762537 17997824 1741 33554432000 4194304 4933572 140735533045760 18446744073709551615 4637201 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 4394 1741 375 181 0 1403 0
Current children cumulated CPU time (s) 25.5
Current children cumulated vsize (KiB) 17576
Solver just ended. Dumping a history of the last processes samples
[startup+31.9206 s]
/proc/loadavg: 1.95 1.99 1.93 3/573 18919
/proc/meminfo: memFree=31958564/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=18092 CPUtime=31.92 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1933 0 0 0 3192 0 0 0 25 0 1 0 818762537 18526208 1870 33554432000 4194304 4933572 140735533045760 18446744073709551615 4330071 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 4523 1870 375 181 0 1532 0
Current children cumulated CPU time (s) 31.92
Current children cumulated vsize (KiB) 18092
[startup+38.3004 s]
/proc/loadavg: 1.95 1.99 1.93 3/573 18919
/proc/meminfo: memFree=31958296/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=18192 CPUtime=38.3 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1948 0 0 0 3830 0 0 0 25 0 1 0 818762537 18628608 1885 33554432000 4194304 4933572 140735533045760 18446744073709551615 4632799 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 4548 1885 375 181 0 1557 0
Current children cumulated CPU time (s) 38.3
Current children cumulated vsize (KiB) 18192
[startup+41.5007 s]
/proc/loadavg: 1.96 1.99 1.93 3/573 18919
/proc/meminfo: memFree=31958172/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=18192 CPUtime=41.5 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1962 0 0 0 4150 0 0 0 25 0 1 0 818762537 18628608 1899 33554432000 4194304 4933572 140735533045760 18446744073709551615 4319463 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 4548 1899 375 181 0 1557 0
Current children cumulated CPU time (s) 41.5
Current children cumulated vsize (KiB) 18192
[startup+42.3006 s]
/proc/loadavg: 1.96 1.99 1.93 3/573 18919
/proc/meminfo: memFree=31958172/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=18192 CPUtime=42.3 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1962 0 0 0 4230 0 0 0 25 0 1 0 818762537 18628608 1899 33554432000 4194304 4933572 140735533045760 18446744073709551615 4717456 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 4548 1899 375 181 0 1557 0
Current children cumulated CPU time (s) 42.3
Current children cumulated vsize (KiB) 18192
[startup+42.7006 s]
/proc/loadavg: 1.96 1.99 1.93 3/573 18919
/proc/meminfo: memFree=31958172/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=18192 CPUtime=42.7 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1962 0 0 0 4270 0 0 0 25 0 1 0 818762537 18628608 1899 33554432000 4194304 4933572 140735533045760 18446744073709551615 4649364 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 4548 1899 375 181 0 1557 0
Current children cumulated CPU time (s) 42.7
Current children cumulated vsize (KiB) 18192
[startup+43.1006 s]
/proc/loadavg: 1.96 1.99 1.93 3/573 18919
/proc/meminfo: memFree=31958172/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=18192 CPUtime=43.1 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1962 0 0 0 4310 0 0 0 25 0 1 0 818762537 18628608 1899 33554432000 4194304 4933572 140735533045760 18446744073709551615 4649364 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 4548 1899 375 181 0 1557 0
Current children cumulated CPU time (s) 43.1
Current children cumulated vsize (KiB) 18192
[startup+43.2005 s]
/proc/loadavg: 1.96 1.99 1.93 3/573 18919
/proc/meminfo: memFree=31958172/32950928 swapFree=43925852/67111528
[pid=18917] ppid=18915 vsize=18192 CPUtime=43.2 cores=0,2,4,6
/proc/18917/stat : 18917 (clasp) R 18915 18917 17441 0 -1 4202496 1962 0 0 0 4320 0 0 0 25 0 1 0 818762537 18628608 1899 33554432000 4194304 4933572 140735533045760 18446744073709551615 4319400 0 0 4096 18946 0 0 0 17 4 0 0 0
/proc/18917/statm: 4548 1899 375 181 0 1557 0
Current children cumulated CPU time (s) 43.2
Current children cumulated vsize (KiB) 18192
Child status: 10
Real time (s): 43.2147
CPU time (s): 43.2154
CPU user time (s): 43.2144
CPU system time (s): 0.000999
CPU usage (%): 100.002
Max. virtual memory (cumulated for all children) (KiB): 18224
getrusage(RUSAGE_CHILDREN,...) data:
user time used= 43.2144
system time used= 0.000999
maximum resident set size= 0
integral shared memory size= 0
integral unshared data size= 0
integral unshared stack size= 0
page reclaims= 1978
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= 5
involuntary context switches= 83
runsolver used 0.245962 second user time and 0.554915 second system time
The end
Begin job on node122 at 2011-06-03 05:27:17
IDJOB=3468552
IDBENCH=1394
IDSOLVER=1958
FILE ID=node122/3468552-1307071637
RUNJOBID= node122-1307068797-18483
PBS_JOBID= 13497864
Free space on /tmp= 73808 MiB
SOLVER NAME= clasp 2.0-R4191
BENCH NAME= PB06//final/normalized-PB06/SATUNSAT-SMALLINT/submitted-PB05/aloul/FPGA_SAT05/normalized-fpga15_14_sat_pb.cnf.cr.opb
COMMAND LINE= HOME/clasp BENCHNAME --berk-max=512 --berk-once --otfs=1 --recursive-str --dinit=1500,10000 --dsched=10000,1.1,20000 --restart-on-model --opt-heu=2
RUNSOLVER COMMAND LINE= BIN/runsolver --timestamp -w /tmp/evaluation-result-3468552-1307071637/watcher-3468552-1307071637 -o /tmp/evaluation-result-3468552-1307071637/solver-3468552-1307071637 -C 1800 -W 1900 -M 15500 HOME/clasp HOME/instance-3468552-1307071637.opb --berk-max=512 --berk-once --otfs=1 --recursive-str --dinit=1500,10000 --dsched=10000,1.1,20000 --restart-on-model --opt-heu=2
TIME LIMIT= 1800 seconds
MEMORY LIMIT= 15500 MiB
NBCORE= 4
MD5SUM BENCH= 49aa50e1ed35f3f8c8cb0a8781a76e97
RANDOM SEED=6381389
node122.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 : 2666.820
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 : 5333.64
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 : 2666.820
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 : 5332.75
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 : 2666.820
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 : 2666.820
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 : 5332.83
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 : 2666.820
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 : 2666.820
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 : 5332.75
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 : 2666.820
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 : 5332.75
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 : 2666.820
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 : 5332.97
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: [8]
/proc/meminfo:
MemTotal: 32950928 kB
MemFree: 31967916 kB
Buffers: 252528 kB
Cached: 371724 kB
SwapCached: 16832 kB
Active: 296780 kB
Inactive: 374300 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 32950928 kB
LowFree: 31967916 kB
SwapTotal: 67111528 kB
SwapFree: 43925852 kB
Dirty: 828 kB
Writeback: 0 kB
AnonPages: 44252 kB
Mapped: 9672 kB
Slab: 147468 kB
PageTables: 93520 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
CommitLimit: 83586992 kB
Committed_AS: 180761008 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= 73804 MiB
End job on node122 at 2011-06-03 05:28:01