On Fri, Mar 26, 2010 at 10:00 PM, Kirk Wolf <k...@dovetail.com> wrote:
> Sam, > > I like z/OS as much as the next guy, but I have to disagree with most > of your comparisons. > > On Fri, Mar 26, 2010 at 4:20 PM, Sam Siegel <s...@pscsi.net> wrote: > > > > Then there are things like checkpoint restart. On unix, that is > "something > > the database does". There is now OS level facility that lets you restart > > where you left off. > > > So, you can checkpoint your position in a sequential dataset and > synchronize this with a DB2 commit for convenient restart processing > without buying a third party product? z/OS checkpoint/restart is > pretty archaic IMO. It is much easier to do this on *nux, since a > file pointer is just a number. > > > There are also file system issues. It seems lately that there have been > > many comments regards ckd disk, etc. Consider the flip side. Unix does > not > > have anything close to vsam. If you want keyed file access, you either > use > > a database, ryo or purchase a third party product. Vsam goes a long way > to > > solve many problems. Most unix developers are very surprised at > > vsam's capabilities. > > > There are several popular *free* databases, like MySQL. Not to > mention free b-tree implementations. > Maybe the problem is that *nix developers just don't understand how > cool VSAM is.... > Just explain the details of VSAM SHAREOPTIONS to them, that will > convince them :-) > > > Tapes and tape management are woefully lacking on unix. There are still > > many cases, outside of backup, were tape plays an important role. With a > > unix system, using tape is difficult at best. > > > Seems to me like you have to buy a vendor product on any OS to do tape > management well. > Virtual tape subsystems are the future anyway, and that technology is > more or less platform neutral IMO. > > > Take a look at JCL. Many unix developers don't see the true facility of > > JCL. That is indirect specification of resources. JCL (svc 99, etc.) > > allows a program to address different input and output as well as > printers > > and other external devices without the underlying program knowing which > > specific resource is being used. On Unix you must pass very specific > > information to fopen or open to obtain the resource. A "smart" program > can > > read this information from a configuration file or > > via environment variables. However, there is no standardized way of > doing > > this. This makes every "production" job on a unix machine that much > > more difficult to manage. > > > It is simply done differently on Unix... on Unix you use shell scripts > to parameterize file names as shell variables which are used as > arguments to programs. > If anything, shell scripts are *more* flexible than JCL. (But on > z/OS, you can do both, even in a batch job!) > > You didn't really mention the things that I see as the biggest > advantages of z/OS of Unix: > - massive multiprocessing with great resource management (WLM) > - JES (but I guess you did cover this) > - stability, backwards compatibility, reliability... > > FWIW, did IBM sell more net-new z engines last year for z/OS or for Linux? > > Kirk Wolf > Dovetailed Technologies > http://dovetail.com Kirk, Points made ... Sam > > > > Regards, > > Sam > > > >> > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO > Search the archives at http://bama.ua.edu/archives/ibm-main.html > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
