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193.2.4.4 (Pogovor)
(New page: == Queuing system == As an example let us write a program which calculates a product and a quotient of two numbers. We first create a directory ''test'' where the program will be located:...)
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193.2.4.4 (Pogovor)

 
Vrstica 1: Vrstica 1:
== Queuing system == == Queuing system ==
-As an example let us write a program which calculates a product and a quotient of two numbers. We first create a directory ''test'' where the program will be located:+The queuing system supports two types of jobs: in a '''batch job''' there is no interaction between the user and the job while the job is running. If such an interaction is needed you should ask the queuing system for an '''interactive job'''.
 + 
 +=== Batch jobs ===
 + 
 +As an example let us write a program which waits for two minutes and then calculates a product and a quotient of two numbers. We first create a directory ''test'' where the program will be located:
<code><font color=blue>rejec@atos:~> mkdir test</font> <code><font color=blue>rejec@atos:~> mkdir test</font>
<font color=blue>rejec@atos:~> cd test</font> <font color=blue>rejec@atos:~> cd test</font>
Vrstica 11: Vrstica 15:
print "a = $a\n"; print "a = $a\n";
print "b = $b\n"; print "b = $b\n";
 + print "Waiting for two minutes ...\n";
 + sleep 120;
print "a * b = ", $a * $b, "\n"; print "a * b = ", $a * $b, "\n";
print "a / b = ", $a / $b, "\n";</code> print "a / b = ", $a / $b, "\n";</code>
Vrstica 17: Vrstica 23:
a = 2 a = 2
b = 0 b = 0
 + Waiting for two minutes ...
a * b = 0 a * b = 0
Illegal division by zero at ./programcek line 6.</code> Illegal division by zero at ./programcek line 6.</code>
Vrstica 22: Vrstica 29:
<code><font color=blue>rejec@atos:~/test> cat programcek.sh</font> <code><font color=blue>rejec@atos:~/test> cat programcek.sh</font>
#!/bin/bash #!/bin/bash
 + #PBS -l walltime=00:03:00
cd test cd test
programcek 2 0</code> programcek 2 0</code>
-The shell script should first change the directory to the one where the program itself is located (''cd test''). Then it should run the program (''programcek 2 0'').+In the second line we inform the system that the job will run at most three minutes (''#PBS -l walltime=00:03:00''). If the job takes longer to complete it will be killed. If this line is missing in the shell script the default value of one minute will be used. The shell script should then change the directory to the one where the program itself is located (''cd test''). Then it should run the program (''programcek 2 0'').
Now we are ready to put the program in the queue. This we can do with the ''qsub'' command: Now we are ready to put the program in the queue. This we can do with the ''qsub'' command:
Vrstica 60: Vrstica 68:
JOBNAME USERNAME STATE PROC WCLIMIT QUEUETIME JOBNAME USERNAME STATE PROC WCLIMIT QUEUETIME
- <font color=red>1849 rejec Idle 1 INFINITY Wed Apr 2 18:02:20</font>+ <font color=red>1849 rejec Idle 1 00:03:00 Wed Apr 2 18:02:20</font>
1 Idle Job 1 Idle Job
Vrstica 82: Vrstica 90:
1826 vilfan Running 6 INFINITY Wed Apr 2 09:37:38 1826 vilfan Running 6 INFINITY Wed Apr 2 09:37:38
1827 vilfan Running 4 INFINITY Wed Apr 2 13:32:32 1827 vilfan Running 4 INFINITY Wed Apr 2 13:32:32
- <font color=red>1849 rejec Running 1 INFINITY Wed Apr 2 18:14:18</font>+ <font color=red>1849 rejec Running 1 00:03:00 Wed Apr 2 18:14:18</font>
9 Active Jobs 64 of 96 Processors Active (66.67%) 9 Active Jobs 64 of 96 Processors Active (66.67%)
Vrstica 112: Vrstica 120:
Illegal division by zero at ./programcek line 6.</code> Illegal division by zero at ./programcek line 6.</code>
The output and the errors of the job were saved in the ''programcek.sh.o1849'' and ''programcek.sh.e1849'' files, respectively. The output and the errors of the job were saved in the ''programcek.sh.o1849'' and ''programcek.sh.e1849'' files, respectively.
 +
 +=== Interactive jobs ===
 +
 +Use the following command to ask the queuing system for a two hour interacting job:
 +
 + <code><font color=blue>rejec@atos:~/test/> qsub -l walltime=02:00:00 -I</font>
 + qsub: waiting for job 12813.atos.ijs.si to start
 + qsub: job 12813.atos.ijs.si ready
 +
 + <font color=blue>rejec@n19:~/></font></code>
 +
 +The system found a free processor on the n19 node and opened a shell there. The shell can be used to do whatever you wish for the next two hours.
 +
 +=== Additional information ===
You can find additional information in the [[Media:PBSProUG_5_4_0.pdf|users manual]]. You can find additional information in the [[Media:PBSProUG_5_4_0.pdf|users manual]].

Trenutna redakcija

Vsebina

[spremeni] Queuing system

The queuing system supports two types of jobs: in a batch job there is no interaction between the user and the job while the job is running. If such an interaction is needed you should ask the queuing system for an interactive job.

[spremeni] Batch jobs

As an example let us write a program which waits for two minutes and then calculates a product and a quotient of two numbers. We first create a directory test where the program will be located:

rejec@atos:~> mkdir test
rejec@atos:~> cd test
rejec@atos:~/test> 

Let's call the program programcek. The code in perl is

rejec@atos:~/test> cat programcek
#!/usr/bin/perl
my ($a, $b) = @ARGV;
print "a = $a\n";
print "b = $b\n";
print "Waiting for two minutes ...\n";
sleep 120;
print "a * b = ", $a * $b, "\n"; 
print "a / b = ", $a / $b, "\n";

An example output:

rejec@atos:~/test> programcek 2 0
a = 2
b = 0
Waiting for two minutes ...
a * b = 0
Illegal division by zero at ./programcek line 6.

Now we'll run the program using the queuing system. First we need to write a shell script. Let's call it programcek.sh.

rejec@atos:~/test> cat programcek.sh
#!/bin/bash
#PBS -l walltime=00:03:00
cd test
programcek 2 0

In the second line we inform the system that the job will run at most three minutes (#PBS -l walltime=00:03:00). If the job takes longer to complete it will be killed. If this line is missing in the shell script the default value of one minute will be used. The shell script should then change the directory to the one where the program itself is located (cd test). Then it should run the program (programcek 2 0).

Now we are ready to put the program in the queue. This we can do with the qsub command:

rejec@atos:~/test> qsub programcek.sh
1849.atos.ijs.si

Note that an id number 1849 was assigned to the job. From this point on, you'll be able to check the status of job, stop it and access its results only through the id number. So don't forget it.

Let's check what is going on in the queue with the showq command:

rejec@atos:~/test> showq
ACTIVE JOBS--------------------
JOBNAME            USERNAME      STATE  PROC   REMAINING            STARTTIME

1732                 vilfan    Running     5  3:20:30:14  Tue Apr  1 10:32:35
1646                 vilfan    Running    12    INFINITY  Thu Mar 27 17:09:44
1716                 vilfan    Running     6    INFINITY  Mon Mar 31 17:52:49
1717                 vilfan    Running     6    INFINITY  Mon Mar 31 18:01:39
1739                 vilfan    Running    12    INFINITY  Tue Apr  1 13:36:11
1740                 vilfan    Running    12    INFINITY  Tue Apr  1 14:14:54
1826                 vilfan    Running     6    INFINITY  Wed Apr  2 09:37:38
1827                 vilfan    Running     4    INFINITY  Wed Apr  2 13:32:32
1835                  rejec    Running     4    INFINITY  Wed Apr  2 18:00:22
1836                  rejec    Running    10    INFINITY  Wed Apr  2 18:00:35
1838                  rejec    Running     1    INFINITY  Wed Apr  2 18:00:51
1839                  rejec    Running    10    INFINITY  Wed Apr  2 18:00:57
1841                  rejec    Running     4    INFINITY  Wed Apr  2 18:01:33
1845                  rejec    Running     1    INFINITY  Wed Apr  2 18:01:54
1846                  rejec    Running     1    INFINITY  Wed Apr  2 18:02:03
1847                  rejec    Running     1    INFINITY  Wed Apr  2 18:02:14
1848                  rejec    Running     1    INFINITY  Wed Apr  2 18:02:17

    17 Active Jobs      96 of   96 Processors Active (100.00%)
                        24 of   24 Nodes Active      (100.00%)

IDLE JOBS----------------------
JOBNAME            USERNAME      STATE  PROC     WCLIMIT            QUEUETIME

1849                  rejec       Idle     1    00:03:00  Wed Apr  2 18:02:20

1 Idle Job

BLOCKED JOBS----------------
JOBNAME            USERNAME      STATE  PROC     WCLIMIT            QUEUETIME


Total Jobs: 18   Active Jobs: 17   Idle Jobs: 1   Blocked Jobs: 0

We note that our job is listed under the IDLE JOBS. This means that all the processors are currently occupied and our job has to wait until one of them is free before it can be run. Let's check again few hours later:

rejec@atos:~/test> showq
ACTIVE JOBS--------------------
JOBNAME            USERNAME      STATE  PROC   REMAINING            STARTTIME

1732                 vilfan    Running     5  3:20:18:17  Tue Apr  1 10:32:35
1646                 vilfan    Running    12    INFINITY  Thu Mar 27 17:09:44
1716                 vilfan    Running     6    INFINITY  Mon Mar 31 17:52:49
1717                 vilfan    Running     6    INFINITY  Mon Mar 31 18:01:39
1739                 vilfan    Running    12    INFINITY  Tue Apr  1 13:36:11
1740                 vilfan    Running    12    INFINITY  Tue Apr  1 14:14:54
1826                 vilfan    Running     6    INFINITY  Wed Apr  2 09:37:38
1827                 vilfan    Running     4    INFINITY  Wed Apr  2 13:32:32
1849                  rejec    Running     1    00:03:00  Wed Apr  2 18:14:18

     9 Active Jobs      64 of   96 Processors Active (66.67%)
                        23 of   24 Nodes Active      (95.83%)

IDLE JOBS----------------------
JOBNAME            USERNAME      STATE  PROC     WCLIMIT            QUEUETIME


0 Idle Jobs

BLOCKED JOBS----------------
JOBNAME            USERNAME      STATE  PROC     WCLIMIT            QUEUETIME


Total Jobs: 9   Active Jobs: 9   Idle Jobs: 0   Blocked Jobs: 0

Now the program running: it is listed under the ACTIVE JOBS. If in the meantime you've found out that there is a bug in your program, you should stop it to make the resources available to other users. You can do this with the qdel command:

rejec@atos:~/test> qdel 1849

Let's assume everything was OK with your program, and you'd waited until it stopped running. The results of the calculation are available in the directory where the job was started:

rejec@atos:~/test> ls
programcek  programcek.sh  programcek.sh.e1849  programcek.sh.o1849

rejec@atos:~/test> cat programcek.sh.o1849
a = 2
b = 0
a * b = 0

rejec@atos:~/test> cat programcek.sh.e1849
Illegal division by zero at ./programcek line 6.

The output and the errors of the job were saved in the programcek.sh.o1849 and programcek.sh.e1849 files, respectively.

[spremeni] Interactive jobs

Use the following command to ask the queuing system for a two hour interacting job:

rejec@atos:~/test/> qsub -l walltime=02:00:00 -I
qsub: waiting for job 12813.atos.ijs.si to start
qsub: job 12813.atos.ijs.si ready

rejec@n19:~/>

The system found a free processor on the n19 node and opened a shell there. The shell can be used to do whatever you wish for the next two hours.

[spremeni] Additional information

You can find additional information in the users manual.