On Wed, Sep 20, 2006 at 07:46:54AM +0800, John Summerfield wrote: > I don't really understand what Flex-ES is - I have some idea it's some > hardware-plus-software imitation mainframe.
As I understand it, it's a software emulator. Fundamental Software does have parallel and ESCON channel hardware to attach real devices, and there's a dongle that's used to authorize execution of the program. > With Hercules, one can in principle choose an 8-way however-many-core > Opteron, or a big Power (or Sparc64/UltraSparc) or other selection from > top500.org. How then would performance compare with Flex-ES? On the same hardware, Flex-ES will outperform Hercules - that is, if it's compiled for the same target. That's because, while Hercules does no emulation in assembler (aside from SMP locking for correctness of execution, which must be done below the level of C), Flex-ES does a lot of its emulation in hand-tuned assembler. This, as Adam noted, was a deliberate design decision, made for portability reasons in the case of Hercules. I do not know if there's a version of Flex-ES that's had its 64-bit emulation recoded from x86 to x86-64. I would not be surprised if Hercules compiled for x86-64 would outperform Flex-ES built for x86 for the same 64-bit workload, but I am not in a position to do more than guess at that. A nice fast 8-way Opteron would probably outrun the average PartnerWorld Flex-ES box, but that's hardly an apples-to-apples comparison. :-) -- Jay Maynard, K5ZC http://www.conmicro.cx http://jmaynard.livejournal.com http://www.tronguy.net http://www.hercules-390.org (Yes, that's me!) Buy Hercules stuff at http://www.cafepress.com/hercules-390 ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
