hfs VS zfs
Ward, Mike S
planning we are trying to decide if we want to go to zfs instead of the
hfs. Is there anyone out there that can think of any good reasons not to
go to zfs when we do our upgrade?
==========================
This email and any files transmitted with it are confidential and intended
solely for the use of the individual or entity to which they are
addressed. If you have received this email in error please notify the
system manager. This message contains confidential information and is
intended only for the individual named. If you are not the named
addressee you should not disseminate, distribute or copy this e-mail.
Please notify the sender immediately by e-mail if you have received
this e-mail by mistake and delete this e-mail from your system. If you
are not the intended recipient you are notified that disclosing, copying,
distributing or taking any action in reliance on the contents of this
information is strictly prohibited.
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to list...@bama.ua.edu with the message: GET IBM-MAIN INFO
Search the archives at http://bama.ua.edu/archives/ibm-main.html
Jerry Whitteridge
> From: IBM Mainframe Discussion List
> [mailto:IBM-...@bama.ua.edu] On Behalf Of Ward, Mike S
> Sent: Monday, January 04, 2010 8:41 AM
> To: IBM-...@bama.ua.edu
> Subject: hfs VS zfs
>
> Hello all, we are planning to migrate from z/os 1.7 to 1.11.
> In our planning we are trying to decide if we want to go to
> zfs instead of the hfs. Is there anyone out there that can
> think of any good reasons not to go to zfs when we do our upgrade?
Most noticeable issue will be if you use indirect cataloging of the systems HFS files (for example locating them on the system res packs set). This is not available for zFS at this time. Due to this we have a mix of zFS and HFS files. SMPE owned and maintained files are HFS and roll with the system res vols. User and Application files are zFS
"Email Firewall" made the following annotations.
------------------------------------------------------------------------------
Warning:
All e-mail sent to this address will be received by the corporate e-mail system, and is subject to archival and review by someone other than the recipient. This e-mail may contain proprietary information and is intended only for the use of the intended recipient(s). If the reader of this message is not the intended recipient(s), you are notified that you have received this message in error and that any review, dissemination, distribution or copying of this message is strictly prohibited. If you have received this message in error, please notify the sender immediately.
==============================================================================
McKown, John
> From: IBM Mainframe Discussion List
> [mailto:IBM-...@bama.ua.edu] On Behalf Of Jerry Whitteridge
> Sent: Monday, January 04, 2010 12:21 PM
> To: IBM-...@bama.ua.edu
> Subject: Re: hfs VS zfs
>
> > -----Original Message-----
> > From: IBM Mainframe Discussion List
> > [mailto:IBM-...@bama.ua.edu] On Behalf Of Ward, Mike S
> > Sent: Monday, January 04, 2010 8:41 AM
> > To: IBM-...@bama.ua.edu
> > Subject: hfs VS zfs
> >
> > Hello all, we are planning to migrate from z/os 1.7 to 1.11.
> > In our planning we are trying to decide if we want to go to
> > zfs instead of the hfs. Is there anyone out there that can
> > think of any good reasons not to go to zfs when we do our upgrade?
>
> Most noticeable issue will be if you use indirect cataloging
> of the systems HFS files (for example locating them on the
> system res packs set). This is not available for zFS at this
> time. Due to this we have a mix of zFS and HFS files. SMPE
> owned and maintained files are HFS and roll with the system
> res vols. User and Application files are zFS
>
I cheat. I never do a DASD copy of my DASD. I do a logical DSN copy from DASD to DASD, and I change some of the names as they are copies. What I do it make my "system" UNIX files have the system name and res volume in the DSN.
OMVS.&SYSNAME..&SYSR1..ROOT
for example. That way, I don't need indirect cataloging. in BPXPRMnn
ROOT FILESYSTEM('OMVS.&SYSNAME..&SYSR1..ROOT')
TYPE(ZFS) MODE(RDWR)
The same with some PARMLIBs, which I put as the __first__ PARMLIB in the concatenation. Like: SYS1.&SYSNAME..PARMLIB. Ditto for special LPALIBs and LINKLIBs. Which, again, I put __first__ so that modules in them override the IBM modules of the same name. Things like ICEAMn.
--
John McKown
Systems Engineer IV
IT
Administrative Services Group
HealthMarkets(r)
9151 Boulevard 26 * N. Richland Hills * TX 76010
(817) 255-3225 phone * (817)-961-6183 cell
john....@healthmarkets.com * www.HealthMarkets.com
Confidentiality Notice: This e-mail message may contain confidential or proprietary information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. HealthMarkets(r) is the brand name for products underwritten and issued by the insurance subsidiaries of HealthMarkets, Inc. -The Chesapeake Life Insurance Company(r), Mid-West National Life Insurance Company of TennesseeSM and The MEGA Life and Health Insurance Company.SM
Schwarz, Barry A
Since zFS is VSAM, we had to adjust our pack cloning procedures but once we worked out the kinks it became a non-issue.
-----Original Message-----
From: IBM Mainframe Discussion List [mailto:IBM-...@bama.ua.edu] On Behalf Of Ward, Mike S
Sent: Monday, January 04, 2010 8:41 AM
To: IBM-...@bama.ua.edu
Subject: hfs VS zfs
Hello all, we are planning to migrate from z/os 1.7 to 1.11. In our
planning we are trying to decide if we want to go to zfs instead of the
hfs. Is there anyone out there that can think of any good reasons not to
go to zfs when we do our upgrade?
----------------------------------------------------------------------
Ted MacNEIL
go to zfs when we do our upgrade?
I would do z/FS as a separate project, either before or after.
Moving from an unsupported release level to a bigger jump than supported by IBM will be complex enough.
-
Too busy driving to stop for gas!
Richard Peurifoy
<barry.a...@BOEING.COM> wrote:
>On a z9 BC running z/OS 1.8, there is a noticeable (~2 minutes) pause in the
IPL sequence while zFS "initializes," accompanied by a non-scrollable message
on the log that eventually does clear. We don't IPL that often so it is not a
big deal for us.
This is probably cause becaue the file system hadn't been properly shutdown.
This causes the file system to be verified when starting.
If you issue
F OMVS,STOPPFS=ZFS
before you finish shutting the system down, I think it will come up faster.
--
Richard
McKown, John
> From: IBM Mainframe Discussion List
> Sent: Monday, January 04, 2010 3:27 PM
> To: IBM-...@bama.ua.edu
> Subject: Re: hfs VS zfs
>
>
> This is probably cause becaue the file system hadn't been
> properly shutdown.
> This causes the file system to be verified when starting.
>
> If you issue
>
> F OMVS,STOPPFS=ZFS
>
> before you finish shutting the system down, I think it will
> come up faster.
>
> --
> Richard
Is that needed even if I do
F OMVS,SHUTDOWN
??
--
John McKown
Systems Engineer IV
IT
Administrative Services Group
HealthMarkets(r)
9151 Boulevard 26 * N. Richland Hills * TX 76010
(817) 255-3225 phone * (817)-961-6183 cell
john....@healthmarkets.com * www.HealthMarkets.com
Confidentiality Notice: This e-mail message may contain confidential or proprietary information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. HealthMarkets(r) is the brand name for products underwritten and issued by the insurance subsidiaries of HealthMarkets, Inc. -The Chesapeake Life Insurance Company(r), Mid-West National Life Insurance Company of TennesseeSM and The MEGA Life and Health Insurance Company.SM
----------------------------------------------------------------------
Richard Peurifoy
<John....@HEALTHMARKETS.COM> wrote:
>> -----Original Message-----
>> From: IBM Mainframe Discussion List
>> [mailto:IBM-...@bama.ua.edu] On Behalf Of Richard Peurifoy
>> Sent: Monday, January 04, 2010 3:27 PM
>> To: IBM-...@bama.ua.edu
>> Subject: Re: hfs VS zfs
>>
>> On Mon, 4 Jan 2010 12:07:22 -0800, Schwarz, Barry A
>> <barry.a...@BOEING.COM> wrote:
><snip>
>>
>> This is probably cause becaue the file system hadn't been
>> properly shutdown.
>> This causes the file system to be verified when starting.
>>
>> If you issue
>>
>> F OMVS,STOPPFS=ZFS
>>
>> before you finish shutting the system down, I think it will
>> come up faster.
>>
>> --
>> Richard
>
>Is that needed even if I do
>
>F OMVS,SHUTDOWN
I think so, but am not positive. We haven't been runnuing
ZFS very long, and I have not experimented a great deal.
If the file system has not been properly shutdown, you get
the following sequence of messages for each file that was open:
IOEZ00397I recovery statistics for ....ETC:
IOEZ00391I Elapsed time was 14 ms
IOEZ00392I 1 log pages recovered consisting of 2 records
IOEZ00393I Modified 1 data blocks
IOEZ00394I 1 redo-data records, 0 redo-fill records
IOEZ00395I 0 undo-data records, 0 undo-fill records
IOEZ00396I 0 not written blocks
IOEZ00400I 0 blocks zeroed
--
Richard
McKown, John
> From: IBM Mainframe Discussion List
> [mailto:IBM-...@bama.ua.edu] On Behalf Of Richard Peurifoy
> Sent: Monday, January 04, 2010 3:53 PM
> To: IBM-...@bama.ua.edu
> Subject: Re: hfs VS zfs
<snip>
> >Is that needed even if I do
> >
> >F OMVS,SHUTDOWN
>
> I think so, but am not positive. We haven't been runnuing
> ZFS very long, and I have not experimented a great deal.
>
> If the file system has not been properly shutdown, you get
> the following sequence of messages for each file that was open:
>
> IOEZ00397I recovery statistics for ....ETC:
> IOEZ00391I Elapsed time was 14 ms
> IOEZ00392I 1 log pages recovered consisting of 2 records
> IOEZ00393I Modified 1 data blocks
> IOEZ00394I 1 redo-data records, 0 redo-fill records
> IOEZ00395I 0 undo-data records, 0 undo-fill records
> IOEZ00396I 0 not written blocks
> IOEZ00400I 0 blocks zeroed
>
> --
> Richard
Thanks for the info. I've never seen those messages.
--
John McKown
Systems Engineer IV
IT
Administrative Services Group
HealthMarkets(r)
9151 Boulevard 26 * N. Richland Hills * TX 76010
(817) 255-3225 phone * (817)-961-6183 cell
john....@healthmarkets.com * www.HealthMarkets.com
Confidentiality Notice: This e-mail message may contain confidential or proprietary information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. HealthMarkets(r) is the brand name for products underwritten and issued by the insurance subsidiaries of HealthMarkets, Inc. -The Chesapeake Life Insurance Company(r), Mid-West National Life Insurance Company of TennesseeSM and The MEGA Life and Health Insurance Company.SM
----------------------------------------------------------------------
Scott Chapman
benchmark-type tasks that used ZFS vs. HFS when both were caching
equally. That pattern was later confirmed with one or two real
workloads. According to IBM this is not really unexpected because ZFS
does more (journaling, more sophisticated caching), but I still was
surprised--it was something on the order of 10% and for workloads
that were doing a *lot* of HFS/ZFS cache friendly reads it did result in
measurably longer run times.
Nonetheless, we're slowly moving towards ZFS because it does a
better job caching than HFS. In fact, HFS caching is flat broken for us
at times and IBM is not particularly interested in fixing it because they
want everybody to go to ZFS. (E.G. I still have an ETR open with them
that's been open for something like 18+ months, waiting for L3 to have
time to work on finding the problem.) So despite the increased CPU
time for similarly cached workloads, workloads that are not being
cached well in HFS may be cached better in ZFS and may have a
significant performance improvement.
The cache reporting and controls in ZFS are also much better. So it's
not all bad, I just wish there wasn't such a significant CPU hit for
things that are already well-cached.
And we did move the root to ZFS.
Jim Marshall
>planning we are trying to decide if we want to go to zfs instead of the
>go to zfs when we do our upgrade?
The suggestion about waiting until you get to 1.11 is stellar and decrease the
complexity by some factor.
In general I attended SHARE a few years ago when going to zFS was the Hot
Topic. We had converted totally over to zFS. Seems to me IBM said the future
was zFS and HFS was being phased out. Kinda stopped looking for the drop-
dead date after that. Maybe the direction has changed to keep both around.
In general at the time, the hot topic was having many, many, many, many,
etc, objects in one zFS directory and the lookup to find the member ATE your
CPU alive in a Parallel Sysplex. IBM promised they were looking into improving
that performance. Until it was redesigned it was "Don'ta do it" or if it hurts to
touch it, do not touch it. Hopefully that problem has been addressed.
jim