topic Re: moving data from one drive to another and the file size change in Operating System - OpenVMS

moving data from one drive to another and the file size change

Scc_3 — Tue, 03 Jan 2006 12:01:54 GMT

Hi Mr. Hein Van Den,

Wow, that is interesting to learn this command. I usually ana/rms/fdl before.

Hello All,
Happy New Year.

I have a question :
I preform the following on dka100: (drive)

Ana/rms/fdl oheadr.trs
edit/fdl/noint oheadr.trs
convert oheadr.trs oheadr.trstest

After convert the file change from 65790(BLOCK) TO 1709
But when I copy the same file and backup to other drive (dka400:) the size change back to 65790.
Is that normal.
Scc

Re: moving data from one drive to another and the file size change

Robert_Boyd — Tue, 03 Jan 2006 12:12:19 GMT

Scc,

If you do a SHOW DEVICE DKA400, what do you see as the CLUSTER SIZE for the device? Compare that to the output of SHOW DEVICE DKA100. The CLUSTER size is the minimum amount of disk space that will be allocated to create a file.

If the cluster size is the same, then my question would be: What happens if you do the same analyze, edit, and convert to the file on DKA400?

Robert

Re: moving data from one drive to another and the file size change

Hein van den Heuvel — Tue, 03 Jan 2006 12:20:53 GMT

fyi: This is changed subject branch from an earlier discussion:

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=976275

Anyway,

This may be a simple confusion between allocated and used file size.
Check out DIR/SIZE=ALL for the and files.

For indexed files the EOF is largely irrelevant, but some tools set it, some don't.

Often is is pointless to reduce the file allocated size, even though you might not use all data right away, but eventually you will.

If the EDIT/FDL/NOINT phase did not do exactly what you want, then by all means go in and hand-edit selected values like the ALLOCATION and EXTENT in the AREA section(s).

Similar topics have been discussed before.
Check out articles like found by:

http://groups.google.com/groups?as_q=allocated+convert&num=10&scoring=r&hl=en&as_epq=file+size&as_oq=&as_eq=&as_ugroup=comp.os.vms

Or here in this forum:
google for: +site:itrc.hp.com +rms +eof +allocated

hth,
Hein.

btw... my official last name is "van den Heuvel", but here in the US I often used vandenheuvel.

Re: moving data from one drive to another and the file size change

Uwe Zessin — Tue, 03 Jan 2006 12:23:43 GMT

If I remember correctly, you are dealing with indexed files...

> After [[convert]] the file change from 65790(BLOCK) TO 1709

Because CONVERT rebuilds the internal structure of the file and removes any data no longer needed.

> But when I [[copy]] the same file and backup to other drive (dka400:)
> the size change back to 65790.

Which *same file*? Do you mean the file with 1709 blocks is recreated with 65790 blocks??

If you choose the original file: it is the same size, because COPY does not touch the contents of the files - it copies all blocks.

Re: moving data from one drive to another and the file size change

Scc_3 — Tue, 03 Jan 2006 12:51:07 GMT

Hello All,
The custer size for both drive is 3.
And if I preform the same ana/rms/fdl.....
on dka400: it convert to 1709.
Looks to me, when I copy the file from dka100: (oheadr.trs) after I run the ana/rms/fdl.... to dka400: it change the block size back to orginal. Or maybe dka100: is a scsi seagate HD and the dka400: is a RZ25.
Thanks !
Scc

Re: moving data from one drive to another and the file size change

Rinkens — Wed, 04 Jan 2006 05:07:12 GMT

Ana/rms/fdl oheadr.trs
edit/fdl/noint oheadr.trs
convert oheadr.trs oheadr.trstest

So you create a new file oheadr.trstest and this one is 1709 blocks.

The orignal one oheadr.trs is 65790 block.

Do you not, by mistake, copy the
orignal oheadr.trs to dka400. According to you last replay you did this.

Re: moving data from one drive to another and the file size change

faris_3 — Wed, 04 Jan 2006 07:43:24 GMT

Hi Scc,

Are you doing a convert or convert/fdl ?

Is the question about why convert changes the size of the file ?
It does to optimize its structure but keeps all the data records.

For example :
$ dir /size=all test.idx

TEST.IDX;7 1085/1085

$ anal/rms/fdl test.idx
$ edit/fdl/nointer test.fdl
$
$ diff test.fdl

TEST.FDL;2
AREA 0
ALLOCATION 140

AREA 1
ALLOCATION 105

AREA 2
ALLOCATION 630

TEST.FDL;1

AREA 0
ALLOCATION 350

AREA 1
ALLOCATION 105

AREA 2
ALLOCATION 630

$
$ convert/fdl=test/stat test.idx test2.idx CONVERT Statistics
Number of Files Processed: 1
Total Records Processed: 80
Buffered I/O Count: 41
Total Exception Records: 0
Direct I/O Count: 178
Total Valid Records: 80
Page Faults: 105
Elapsed Time: 0 00:00:00.74
CPU Time: 0 00:00:00.04
$
$ dir /size=all test2.idx, test.idx

TEST2.IDX;1 875/875
TEST.IDX;7 1085/1085

Re: moving data from one drive to another and the file size change

Wim Van den Wyngaert — Wed, 04 Jan 2006 07:48:15 GMT

Scc,

Simply do set host/log=xxx.txt and do your operation again.

Then post xxx.txt

Wim