On Thu, 25 Dec 2014 22:29:07 +, Blaicher, Christopher Y. wrote:
BSAM gets the length of the block to write from the DCB BLKSIZE at the time of
the WRITE. As long as the DCB BLKSIZE is equal to or less than the max
BLKSIZE all is OK. BSAM will build the CCHHRKDD from the various values it
At 10:49 -0600 on 12/27/2014, Paul Gilmartin wrote about Re: BDW
length vs. Physical Length:
It's a pity that QSAM doesn't routinely exploit track balances.
I agree. It is a waste of track space when the access method refuses
to write short blocks just to keep all but the last block
Equally, it could be argued that the FBA DASD used to emulate ECDKD is
in most cases not really 'spinning' DASD at all; but Christopher
Blaicher was unassailably right when he said that emulated ECKD
devices are what z/OS
DASD controllers.see.
If one finds it amusing to do so, the reductionist
In
b6c1eb4364c30e47950e0f68ef65f467a3561...@proditmailbox1.us.syncsort.com,
on 12/25/2014
at 10:29 PM, Blaicher, Christopher Y. cblaic...@syncsort.com
said:
A Count field with key and data lengths of zero is an EOF marker.
The key length is irrelevant; any record with a zero data length is
In
CAE1XxDE1FGTt0Xg9Aea1tDFUHiJhz8CsYh7WHCXe0t2TZqG=7...@mail.gmail.com,
on 12/26/2014
at 05:25 AM, John Gilmore jwgli...@gmail.com said:
Equally, it could be argued that the FBA DASD used to emulate
ECDKD (sic) is in most cases not really 'spinning' DASD at all;
AFAIK that is not true yet,
My implicit qualification to z/Architecture contexts should have been
explicit, Elsewhere rotating DASD continues in significant use. It
is, however, all but irrelevant to the current discussion
John Gilmore, Ashland, MA 01721 - USA
On Wed, 24 Dec 2014 19:18:44 -0500 Robert A. Rosenberg hal9...@panix.com
wrote:
:At 22:59 + on 12/23/2014, Blaicher, Christopher Y. wrote about
:Re: BDW length vs. Physical Length:
:I can't remember, but BSAM may, and I stress may, check the block
:length is a multiple of the LRECL
I have to question the accuracy of Mr. Altmark's comment. First let's take
the last question from Paul Gilmartin.
ECKD, which is what all modern DASD is, stands for Extended Count Key Data.
The 'Extended' refers to the channel commands you can issue, not the devices
capabilities. All
cblaic...@syncsort.com (Blaicher, Christopher Y.) writes:
ECKD, which is what all modern DASD is, stands for Extended Count Key
Data. The 'Extended' refers to the channel commands you can issue,
not the devices capabilities. All blocks written to a ECKD device
consist of a Count field, an
:58 PM
To: IBM-MAIN@LISTSERV.UA.EDU
Subject: Re: BDW length vs. Physical Length
cblaic...@syncsort.com (Blaicher, Christopher Y.) writes:
ECKD, which is what all modern DASD is, stands for Extended Count Key
Data. The 'Extended' refers to the channel commands you can issue,
not the devices
On 2014-12-23, at 15:59, Blaicher, Christopher Y. wrote:
QSAM and V/VB/VBS format requires a well formed block. The BDW must equal
the total of the RDW's +4. The +4 is for the BDW. You mess that up and QSAM
will throw an error. As long as the BDW is equal to or less than the
BLKSIZE,
At 22:59 + on 12/23/2014, Blaicher, Christopher Y. wrote about
Re: BDW length vs. Physical Length:
I can't remember, but BSAM may, and I stress may, check the block
length is a multiple of the LRECL.
This would only be applicable to FB
PM
To: IBM-MAIN@LISTSERV.UA.EDU
Subject: Re: BDW length vs. Physical Length
In the absence of a truly informed response, I'll take a stab. I learned that a
(QSAM) I/O request specifying a block size less than the actual size-of-block
results in an abend/RC that describes the error. OTOH
I should have mentioned, See Chapter 20 of DFSMS Using Data Sets
Chris Blaicher
Principal Software Engineer, Software Development
Syncsort Incorporated
50 Tice Boulevard, Woodcliff Lake, NJ 07677
P: 201-930-8260 | M: 512-627-3803
E: cblaic...@syncsort.com
For RECFM=V(B)(S), what happens if the physical length of a block
exceeds the length in the BDW?
o Bytes in the physical block beyond the length in the BDW are ignored?
(A writer on another list tells me I can rely on this.)
o The access method reports an error?
I prefer to follow the rules.
-7535 Office
323-715-0595 Mobile
jo.skip.robin...@sce.com
-Original Message-
From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf
Of Paul Gilmartin
Sent: Monday, December 22, 2014 8:37 AM
To: IBM-MAIN@LISTSERV.UA.EDU
Subject: BDW length vs. Physical Length
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