>Remember, z/OS emulates UNIX -- a CAT/READ/de-allocate is still >just as expensive. > >It may quack like a duck; walk like a duck; it is an emulated duck.
There is no such thing as allocation and deallocation in UNIX, incluiding z/OS UNIX. The z/OS UNIX kernel, more specifically, the physical file system code allocates and opens file system data sets at mount time. Thereafter it fullfills all the I/O requests from UNIX processes. I don't see an emulation here. I/O is expensive, no matter what kind of "file system" lies behind it. I haven't done any research on this but I bet in terms of resource usage doing a "UNIX" read is not to much different to doing an "MVS" read. -- Peter Hunkeler Credit Suisse ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
