Ed, Ed. Ed. what are you amazed about exactly?
The instant snap is still an instant snap - nothing in this thread changes that. In fact it reinforces the concept with the statement "copy is immediately available before the physical tracks are copied". You really don't understand this stuff, do you. Ron > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On > Behalf Of Ed Gould > Sent: Saturday, 11 March 2006 1:18 PM > To: IBM-MAIN@BAMA.UA.EDU > Subject: Re: IXFP No Longer Supported > > On Mar 8, 2006, at 9:42 AM, Bruce Black wrote: > > >> > >> I understand the idea that > >> the copy is immediately available before the physical tracks are > >> copied > >> and was just wondering what kind of impact the background copy would > >> have on the foreground tasks running against the same physical disks. > > Rex, that is an interesting question on which I have seen very > > little data. All of the replication technologies which depend on a > > background copy (almost all of them) have to have some impact on > > performance. I am told that the background copies are generally > > lower priority than host-initiated I/Os, but I have to believe that > > they have some impact. If you start the copies for hundreds of > > volumes simultaneously (such as when you are initiating point-in- > > time backups) all that I/O has to have an impact on normal I/O. > > But I have never seen any vendor or user speak of it. Hopefully > > that means that it is just not noticeable. > > > > Call me amazed... but not long ago on here.. this was instantaneous.. > now its some amount of time.. Did there just happen to by a hole in > the space time continuum (and only for certain people?). > > Ed > > ---------------------------------------------------------------------- > 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 ---------------------------------------------------------------------- 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
