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What is the max block size

 
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rambabu
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PostPosted: Mon May 09, 2005 4:52 pm    Post subject: What is the max block size
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what is the max block size?
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superk

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PostPosted: Mon May 09, 2005 6:16 pm    Post subject: Re: blksize
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rambabu wrote:
what is the max block size?

Of what?
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Rajen

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PostPosted: Mon May 09, 2005 6:55 pm    Post subject:
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i think it is 32760
Thanks
Raj
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anil_koneti

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PostPosted: Sat May 14, 2005 11:25 am    Post subject: re
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yes my friend
rajen is correct
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grepusr3

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PostPosted: Sun May 15, 2005 7:00 pm    Post subject: Re: What is the max block size
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Maximum allocated blocksize depends on your DASD devices, disk geometry and your record length. The allocation is based on CKD devices. Most modern DASD (Fixed Block Architecture) emulates CKD models. For optimum allocation, try coding BLKSIZE=0 in the DCB when creating your dataset (the system will define the block size for you).

Using BLKSIZE=32760 on a 3390-3 DASD may create a mucho wasted space, since it is not a whole multiple of track size. Try to allocate block size that is when multiplied (factored), it is as close to the Track Size (56,664) as possible.

For BLKZISE=32760, unallocated space per track = (56,664 - 32,760) = 23,904 bytes

Code:

                  3390 DASD/Disk Information

DASD Model____________ |__3390-2 |____3390-3 |____3390-9 |____3390-27

Track Size in Bytes___ |__56,664 |____56,664 |____56,664 |_____56,664
Tracks per Cylinder___ |______15 |________15 |________15 |_________15
Tracks per Volume_____ |__33,390 |____50,085 |___150,255 |____450,765
Cylinders per Volume__ |___2,226 |_____3,339 |____10,017 |_____30,051
Bytes per Cylinder____ |_849,960 |___849,960 |___849,960 |____849,960
Bytes per Volume______ |_1.89_GB |___2.84_GB |___8.51_GB |___25.53_GB



-Pelad
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