Guys, A little lost on the point of this thread , not trying be rude or flippant , just I see a lot about performance, is it valid with today's hardware and software, yes there is time sensitive events and software and hardware.
Scott ford www.identityforge.com On May 16, 2012, at 4:35 PM, Mike Schwab <[email protected]> wrote: > The Hercules group did some testing comparing MVCL to MVC. > If both source and destination had the same alignment to a double word > boundary, you could move 8 bytes, then increment the 4 registers to > reflect this, before being interuptable. If they aligned differently > between boundaries, each 8 bytes would do this twice. > > Whereas an MVC would do 256 bytes or less without interupting or > touching registers, and was much faster. > > Of course, emulation is much different from hardware, ie, updating all > 4 registers at once. > > On Wed, May 16, 2012 at 2:41 PM, Bernd Oppolzer > <[email protected]> wrote: >> First, I would like to thank you for starting this thread. >> >> I posted it to the performance people of my customer, and they told me, that >> they just found a similar problem with EP PL/1 3.9, that is: the PLIMOVE >> calls >> don't generate MVCLs any more, as in previous releases, but series of MVCs >> and loops. Even when the length of PLIMOVE is - for example - 8000 bytes. >> They discovered it, because one of the PLIMOVE locations showed up in a >> Strobe report. >> >> I asked them to test using a ASSEMBLER program, if the MVC loop is faster, >> but they told me, that even with lengths around 500 or 600, the MVCL >> solution is faster >> - this is on a z196. I have still to confirm this. >> >> If this turns out to be true, this sounds like a bug, and we will try to >> convince IBM to go back to >> the previous solution. If we compile our modules during normal service using >> EP PL/1 3.9, >> our system will get slower and slower, because PLIMOVE is widely used. >> This is not acceptable. >> >> Because the PLIMOVEs are generated by a site-specific macro called PLICOPY, >> I already thought about calling a short ASSEMBLER routine (with minimal >> linkage conventions) >> doing the transfer using MVCL instead of CALL PLIMOVE. The applications need >> not >> to be changed, because the PLICOPY syntax stays the same. Maybe this could >> still be >> faster than doing the MVC loop. >> >> Kind regards >> >> Bernd > > > -- > Mike A Schwab, Springfield IL USA > Where do Forest Rangers go to get away from it all? > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
