Friday, March 26, 2010

Platform comparison - Building a business case for the mainframe

At the beginning of the week there was a thread at the IBM-Main Discussion list about 'Platform Comparison'. It points to a Share presentation by Marlin Maddy of IBM : 'Building the business case for System z'. Apparently there's also a webcast of it via Share online. If you are looking for some solid arguments for making up a business case for the mainframe as compared to your distributed environment, you can really find quite some inspiration here. I know I don't have to convince you about this, but you and I have to convince other people, managers, CFOs etc. that the mainframe is a valid ànd cost effective alternative. No, alternative is not the right word, it's our first choice, of course.

The presentation also points to a series of videos on IBM TV, where Marlin Maddy more or less gives the same exposé. It's actually a six part series and I especially find that the fifth one gives you lots of comparison details, some of which can be easily overlooked, but that really add up to the value of the mainframe. Scroll down in the right column to find all 'episodes'.

A very good addition to this, is this article by John Schlosser (IBM): 'Six Easy Pieces: How to Do Cost of Ownership Analysis Better'. Do take a look at it, it's really worth your time.

Tuesday, March 23, 2010

Short takes

Catching up again with some short messages on the New Mainframe Executive Magazine, a definition of Cloud computing, an article on z/OS deduplication, CA May Mainframe madness and SELCOPY/i.
  • The New Mainframe Executive Magazine for March/April is out. A couple of articles I liked : The consolidation experiences to Linux on System z by the Italian Gruppo Api, an interview with Reed Mullen with a more high-level approach on Linux on System z plus the various Solutions IBM is offering for it and 'Tape a collapsing star' by Randy Chalfant stating : "(...) tape will die because it can't follow or match current market conditions and requirements (...) users will simply stop writing data to tape; they'll opt for disk instead'. Want to find out more : you can download the .pdf over here.
  • This is why I like reading James Governor's Monkchips. The definition of Cloud Computing is actually quite simple : "The next time someone tries to take you through 30 slides explaining the cloud you can just nod sagely, and say… “ohhhh. you mean servers, middleware and apps. Yeah I get it.” A true adherent of cloud computing !
  • I wrote a little article on Protectier deduplication in our System z Newsletter and put it also on this blog. If you want to get a little more in-depth insights on z/OS Deduplication and on deduplication workload characterization, the you might want to take a look at this paper in the published papers section of the Performance Associates site : 'z/OS Data De-de-de-de-duplication' by Dr. Pat Artis.
  • Perhaps a bit early to already call it a tradition but here's CA May Mainframe Madness 2010. You can register over here.
  • It's not my habit to talk about third party products, but this one brought back some nice memories for me. I remember a time when there was ISPF for Windows. Perhaps it still exists and there are still people using it, I wouldn't know. But now I had a mail about a "windows style desktop on the mainframe". So, not familiarizing people with Windows by using ISPF; no, more like familiarizing people with z/OS by using Windows. I'm talking about Selcopy/i. So I took a look at their site and found an overview video. It reminded me of my time as a COBOL programmer in the early nineties. I was working for Dolmen at AnHyp at the time and one of my colleages over there, Frank van Aert, had developed or taken over some kind of self-written ISPF application which was called YP or YPN. The basic principle, though, looked pretty much the same, you edited a file and could start all kinds of operations from there on like editing files, doing listcats, jumping to ISPF 3.4 using wildcards, listing often used files, putting your cursor on it and providing all kinds of actions on it depending on the PFkey you were pressing etc. etc. It definitely saved you lots of time, so I eagerly assisted in further developing it. So far for the memories, Selcopy/i goes further than this of course, presenting it all in some windows like environment young people might like and definitely offering much more functionalities than our little application did. If you're interested, just check it out.
    Oops, not such a short take, this one. Perhaps I should try and contact Frank again, it's been a while . . .

Monday, March 15, 2010

ProtecTIER deduplication for mainframe

A couple of weeks ago, with the announcement of Protectier Deduplication for Mainframe, I promised to come back on this. I’ve written an article about it in our RealDolmen System z Newsletter, so I thought I might as well put a slightly reworked version here too. Protectier and XIV are two products IBM bought some time ago to gain market share in the distributed world. So, don’t worry if you haven’t heard a lot about them yet. But now that Protectier is brought to the mainframe environment, it might be time to check out how Protectier can mean something for you too.
I’m going to tell you a little about ProtecTIER, how it works and what advantages this might have for a mainframe client. I’m also going to tell you how it’s connected to the mainframe.

Deduplication Explained

At first sight you can compare the ProtecTIER technology with a tapeless backup solution. It simulates a virtual tape library. And just as the TS7720 Tapeless Virtualization Engine, it writes the data to disk, be it an attached disk system of your own choice. The real value of the ProtecTIER solution lies in its deduplication technology. The illustration below shows you how this is done.

Click on image to see larger version in new window

A word of explanation ? We have three components. The mainframe is connected to the ProtecTIER appliance which in turn is connected to the disk system. An ‘appliance’ is the term which is often used for an integrated complete solution of hardware and software in a rack.

The software used by the ProtecTIER Gateway (server) is called HyperFactor. As you see on the right hand side, some blocks of data have already been written to disk. The Memory Resident Index is used to keep track of the blocks which have been written to disk. You might say that this index contains some kind of key for every block. And as you can gather from the name, this index resides in the internal memory of the ProtecTIER Gateway. The index has a maximum size of 4GB which is large enough to index 1PB of data.

At the upper left side you see some new data blocks which have to be written to the ‘tape library’. They are sent to the ProtecTIER Gateway and the HyperFactor software uses the index to filter out the blocks that have already been written to disk. Because there’s always a tiny possibility that two different data blocks might generate the same key, the blocks are only marked as identical after a bit by bit comparison of the data themselves. In the example six blocks are filtered out. On disk we just write a pointer to the real data. The new blocks are added. That way, a data block is only written
once to disk. With this method, ProtecTIER targets a 25 to 1 ratio or storing an effective 1TB of data for 25TB of data that are written to tape.

One example : every day we take a full backup of 10TB. We have a daily change rate of about 15%. Starting the first day we actually have to write 10TB. Nothing’s filtered out and with a compression rate of 3:1 an actual 3.3TB is written to disk. The next day we take our full backup again. With a change rate of 15% we filter out 85% and we only have to write 15% or 1.5TB to disk. Again with a compression of 3:1, this means 0.5TB. After a week we have 70TB of uncompressed backup data. With ProtecTIER we write 6.3TB (3.3TB + 6x0.5TB) to disk. This is a ~11:1 ratio.

As you can see, this deduplication is always happening inline (at the moment of writing to disk) instead of some competitor’s postprocessing approach.

Connectivity to the mainframe

Click on image to see larger version in new window

In a mainframe environment the TS7680 ProtecTIER Gateway behaves as an Automated Tape Library (ATL) and is treated as such by the mainframe Oerating System. It emulates a maximum of 256 3592 Model J1A drives and you can write 1,000,000 tape images. Each virtual tape has a capacity of 100GB. The ‘library’ has standard DFSMS support. At the host side you don’t have to change applications, tape management systems and/or JCL to support the new ‘library’. De TS7680 requires at least z/OS 1.9 or z/VM 5.3.

You can see an illustration of the technical connectivity below.

Click on image to see larger version in new window

The ProtecTIER Gateway originates from the distributed environment and doesn’t know the FICON protocol. You might say we’ve seen the same before with the TS3500 tape library too. Therefore two control units are placed between the mainframe and the ProtecTIER Gateways. Each control unit has a maximum of four FICON connections. I would call them 3592-C06 controllers but they are nowhere indicated as such. As you can also see we have complete redundancy and failover capabilities for each component. The control units are connected with the ProtecTIER Gateways through Fiber Channel.
What stays the same as in the distributed environment is the choice of the disk system the TS7680 writes to. This can e.g. be a DS8000, but also a DS5000, an XIV or an SVC. The choice is up to you.


Friday, March 12, 2010

Redbook : z/OS V1R11 Implementation . . . is back

I talked about this Redbook some time ago, but then it suddenly disappeared off the radar. Well, it's back now : z/OS Version 1 Release 11 Implementation'. At first sight, I think it's been updated here and there. Let's hope it stays up longer this time.

Thursday, March 11, 2010

RealDolmen System z e-zine N° 15

Watch your mailbox, the 15th issue of our RealDolmen System z Newsletter for our Belgian customers is being sent out at this very moment. As we target the Belgian market, those who read Dutch or French can find this and previous newsletters on the RealDolmen Website : Dutch versions and French Versions. If you don't receive it yet, you can subscribe to it over here. If you have subscribed, but for some reason no longer receive it, please let me know.

We have two main articles : the first one is focusing on the ProtecTIER Deduplication solution for mainframe. The second one gives you an overview of the zRace study. With this TCO study we can give you some ball-park figures when you're interested in moving applications from a distributed environment towards Linux on System z.

As usual there are also some hints, tips, links, an overview of recent announcements, EOS dates of software and operating systems and an agenda for mainly Belgian events.

Enjoy the reading !

Wednesday, March 10, 2010

GSE Belux site

GSE Belux now has its own site :, and I think it's nice to see all information about GSE Belux and its working groups gathered in one site. It will save you lots of searching once every group has abandoned its own little corner (site). The IMS & DB2 Working Group sets the example : all information about the steering committee, upcoming events and downloads from previous events are already there. When all others follow, this will be a great place to gather information.

And don't forget to check out the agenda of 'upcoming events' (hey, sounds familiar) at the upper right corner of the screen.

Nice initiative. So, just check it out !

Friday, March 5, 2010

z/OS 1.12 delivery on tape

You know there was a Statement of Direction from IBM that z/OS would no longer be delivered on 3480 and 3490 tape cartridges. By the way, that is already the case for z/VM. Well, for any one who verified the z/OS 1.12 preview announcement to see whether 3480 and 3490 tape media would still be available : check again. The announcement has been modified in that section. It first mentioned :
Currently offered media types are:
• CBPDOs - 3480, 3480 Compressed, 3490E, 3590, 3592
• ServerPacs - 3480, 3480 Compressed, 3490E, 3590, 3592
• SystemPacs - 3480, 3480 Compressed, 3490E, 3590, 3592
But, it now mentions
You choose the delivery method when you order the software. IBM recommends Internet delivery. In addition to Internet and DVD, the supported tape delivery options for CBPDO, ServerPac, and SystemPac include:

- 3590
- 3592

Note: Product delivery on all 3480 and 3490 tape media is planned to be discontinued October 26, 2010.
So, if you have no choice but ordering on 3480 or 3490 tape media, be sure to order z/OS 1.12 before October 26, 2010.

I missed this one, but thanks to Isabelle Silvain (IBM France) for mentioning this.

Monday, March 1, 2010

Red Alert for all TCPIP users on z/OS 1.11

Here's a Red Alert for all TCPIP users on z/OS 1.11 :

A logic error in the base TCPIP code of z/OS 1.11 can cause applications using ASYNCIO Writes to be driven twice. This can affect various applications and subsystems using z/OS TCPIP ASYNCIO on the sending side, such as Websphere MQ, JES and non-IBM products.

A logic error in TCPIP on z/OS 1.11 can cause applications using ASYNCIO Writes to be driven twice. The application data presented on the socket write operation is sent over the TCP connection twice, thus corrupting the data stream. This can affect various applications and subsystems using z/OS TCPIP ASYNCIO on the sending side, such as Websphere MQ, JES and non-IBM products. Please see APAR PM08514 for the details and symptoms that may result.

Recommended Action:
All z/OS 1.11 users should install the APAR fix for PM08514 that is currently available from IBM Support. This APAR does not apply to prior z/OS releases.

If you want to have en overview of all past Red Alerts, then take a look over here. You can also subscribe on the same page so you'll be notified by mail of any future Red Alert.