John,
I have been told that CFW must be turned off for Hyperswap, but I never
understood why. You say that CFW must be written to disk for Hyperswap,
but
why can all the other writes still be deferred in cache/NVS?
Ron
Hyperswap would be one of those circumstances were you would
SyncSort should use CFW for SORTWK I/O unless the device is not enabled
for it. SORTOUT I/O will use DFW.
John Reda
Syncsort, Inc.
-Original Message-
From: IBM Mainframe Discussion List [EMAIL PROTECTED] On
Behalf Of John Baker
Sent: Friday, January 18, 2008 4:30 PM
To: IBM-MAIN
John,
I have been told that CFW must be turned off for Hyperswap, but I never
understood why. You say that CFW must be written to disk for Hyperswap,
but
why can all the other writes still be deferred in cache/NVS?
Ron
Hyperswap would be one of those circumstances were
In a message dated 1/21/2008 10:39:36 A.M. Central Standard Time,
[EMAIL PROTECTED] writes:
It looks like the GDPS group also misunderstood CFW.
...
Excerpt from GDPS
You should eliminate any known exploitation of Cache Fast Write (CFW).
Disk write operations using CFW (Cache Fast Write)
In a message dated 1/18/2008 8:52:20 P.M. Central Standard Time,
[EMAIL PROTECTED] writes:
Yes, SyncSort does use CFW. I wrote the code myself in a previous life,
17 or so years ago. However, IIRC, there may be circumstances where it is
turned off due to other performance
[mailto:[EMAIL PROTECTED] On
Behalf Of Traylor, Terry
Sent: Saturday, January 19, 2008 6:40 PM
To: IBM-MAIN@BAMA.UA.EDU
Subject: Re: [IBM-MAIN] CFW with Syncsort
Here's the answer to the first half of your question.
Disk write operations using CFW (Cache Fast Write) are written into
cache
:
In a message dated 1/18/2008 8:52:20 P.M. Central Standard Time,
[EMAIL PROTECTED] writes:
Yes, SyncSort does use CFW. I wrote the code myself in a previous life,
17 or so years ago. However, IIRC, there may be circumstances where it is
turned off due to other performance considerations
Yes, SyncSort does use CFW. I wrote the code myself in a previous life,
17 or so years ago. However, IIRC, there may be circumstances where it is
turned off due to other performance considerations. Check with SyncSort's
Customer Service if you need to know when, if ever these days.
Hi
John,
I have been told that CFW must be turned off for Hyperswap, but I never
understood why. You say that CFW must be written to disk for Hyperswap, but
why can all the other writes still be deferred in cache/NVS?
Ron
Hyperswap would be one of those circumstances were you would also want
-MAIN@BAMA.UA.EDU
Subject: Re: CFW with Syncsort
John,
I have been told that CFW must be turned off for Hyperswap, but I never
understood why. You say that CFW must be written to disk for Hyperswap,
but
why can all the other writes still be deferred in cache/NVS?
Ron
Hyperswap would be one
John:
Yes, SyncSort does use CFW. I wrote the code myself in a previous life,
17 or so years ago. However, IIRC, there may be circumstances where it is
turned off due to other performance considerations. Check with SyncSort's
Customer Service if you need to know when, if ever these days
Hi all, hopefully an easy one here.
Can anyone confirm whether or not Syncsort uses CFW? I know DF/Sort does
but I'm not sure about Sync.
Thanks,
JB
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John,
I have been told many times that SYNCSORT uses CFW, but I have never
observed any change in the RMFCR counters when I turn CFW on in a controller
with SYNCSORT Sort Work datasets. For DFSORT my experience is there is a
significant increment in the CFW counter, and a very apparent change
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