UNIT=SILO

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diwz
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UNIT=SILO

Post by diwz » Thu Apr 25, 2013 5:15 pm

As part of best practice & optimization, my site support has asked me to place files that are larger than 1000 CYLs in SILO. When I asked them how to use it. He informed me to use UNIT=SILO. I am not sure on what specific condition it has to be used.

I searched manuals and also in google to get information on SILO in mainframe. Couldn't get much info. I have seen in production environment that UNIT=SILO is used to take backup of files.

My query is , whether it has any performance improvement when compared to TAPE. I couldnot visualize how it is better than other TAPE or others. Please clarify this when you have time.

NicC
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Post by NicC » Thu Apr 25, 2013 7:33 pm

Check with your storage people - they know how SILO is set up in your shop and for what it is to be used. But one would assume that whoever said "do this" has already checked it out so all you have to do is implement it. Which means clarifying with that group when to use that unit "type".
Regards
Nic

DikDude
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Post by DikDude » Thu Apr 25, 2013 9:09 pm

There should be some standard that explains how to use this UNIT= value.

Most places the SILOs are automated tape libraries to be used for large files that do not need to be online (i.e. vsam, database, libraries, etc).

You will need to find out if SILO is for dasd or something else.

As Nic mentioned, you need to work with your storage management people.

If the storage magement people (who "knows these things") provided the direction, suggest you try to run an IEFBR14 to allocate a dataset with UNIt=SILO.
Last edited by DikDude on Tue May 07, 2013 11:08 pm, edited 1 time in total.
Have a good one

diwz
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Joined: Sun Feb 10, 2013 10:39 am

Post by diwz » Fri Apr 26, 2013 10:45 am

Site support is saying that it has been used for storage reduction.

I tried allocating a dataset using IEFBR14 with UNIT=SILO. Job went fine. I could not find the datase in =3.4 options. Its saying that no dataset names are found.

But, dataset with same name and with UNIT=SYSDA is cataloged using IEFBR14. Its strange for me. Could you please clarify if anything I am failing to understand wrt the way SMS works.
Last edited by diwz on Fri Apr 26, 2013 11:20 am, edited 1 time in total.

diwz
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Posts: 44
Joined: Sun Feb 10, 2013 10:39 am

Post by diwz » Fri Apr 26, 2013 11:01 am

Below is the JCL that used

Code: Select all

//STEP01   EXEC  PGM=IEFBR14                            
//SYSPRINT DD  SYSOUT=*                                 
//SYSUDUMP DD  SYSOUT=*                                 
//ABNLTERM DD  SYSOUT=*                                 
//NEWDD    DD DSN=Z332107.UNIT.SILO.TEST4,              
//         DISP=(NEW,CATLG),                      
//         UNIT=SILO,                                   
//         DCB=(LRECL=80,RECFM=F,BLKSIZE=0,DSORG=PS),   
//         SPACE=(CYL,(1,1),RLSE),                      
//         LABEL=(1,SL,,,EXPDT=99000)                   
//*                                                     

NicC
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Location: Down on the pig farm

Post by NicC » Fri Apr 26, 2013 9:41 pm

You will probably find that SILO is for large datasets (100's of CYLs) so SMF has changed your unit to a more appropriate one. It may also be that SILO data needs a specific format of dataset name but only your storage guys'n'gals can tell you that.
Regards
Nic

DikDude
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Post by DikDude » Sat Apr 27, 2013 12:03 am

You might ask your support people How this is used for "storage reduction".

What you have is site-specific and the understanding of what is setup is only with people at your site.
Have a good one

diwz
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Posts: 44
Joined: Sun Feb 10, 2013 10:39 am

Post by diwz » Tue May 07, 2013 1:36 pm

Okay. I will check with the site resources. Thanks DikDude.

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