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How much space i need to allocate for the file

 
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jagankallis
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Joined: 28 Jun 2006
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Location: DUISBURG

PostPosted: Tue Jul 25, 2006 10:37 pm    Post subject: How much space i need to allocate for the file
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Dear Members,

I have a doubt in JCL space allocations. Could you please let me know how much space i need to allocate. I have a file generated by my programs with size as 3000bytes Variable length and ther are approx 4 million records. How much space should i allocates to it.

Please let me know the formulate to calcuates it in cylinders, tracks and blocks.
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superk

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Joined: 26 Apr 2004
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Location: Raleigh, NC, USA

PostPosted: Tue Jul 25, 2006 11:14 pm    Post subject: Re: Space occupied
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Based on our shop's standards, I come up with:
Code:

//         SPACE=(3000,(3953,790),RLSE),AVGREC=K


based on the calculation:

LRECL * MAX # of RECORDS / 56664 = (# of tracks)
3000 * 4,000,000 / 56664 = 211,775 tracks.

BLKSIZE / LRECL * 2 * (# of tracks) = primary space
27,998 / 3000 * 2 * 211775 = 3952851

So, divide 3952851 by 1000, rounding up, and that's the primary. For our shop, the secondary is given as 20% of the primary.
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