On Fri, May 17, 2019 at 07:57:32PM -0400, D. Hugh Redelmeier via talk wrote: > For the CPU's Lennart was talking about, the modern CPU is a little > faster, but no enough to notice > > <http://hwbench.com/cpus/intel-core-i7-8550u-vs-intel-core-i7-3820qm> > > (The i7-8550u is in the NUC; the i7-3820qm is my guess at what > Lennart's ThinkPad W530 has.)
You guess correctly. The desktop machine runs an i7-3960X. It certainly would not be a big leap in performance, and if you touch anything with graphics, the quadro K2000M will beat the intel graphics easily. :) > Desktops are a bit different. But I would not expect even a factor of > two difference in comparable processors of these two generations. > > Which processor models were/are in your (Giles') two systems? > > - DDR4 (8th gen) is faster than DDR3 (required by 3rd gen). But most > programs don't seem to be affected much by this. Does your program > bust the (rather large) L2 cache? As far as I know, DDR4 has more bandwidth but also higher latency, so different work loads are affected differently. > - 3rd gen i5's often have half the cores of 8th gen i5's. This may > make a big difference. But Python programs often don't exploit > multiple cores. Well 3rd gen is usually 4 core (occationally 2) and 8th gen is 6 core. > - a few instructions have been added, but I don't imagine that they > affect your python program. AVX2 for floating point, for example. > > My best guess is that the program sped up due to (NVMe?) SSD vs HDD. Yeah that could easily drop 20m to 5m or more. > Perhap AMD flaws haven't been discovered yet. But the current score > shows AMD ahead. > > My take on rowhammer is that it is a bug in the DRAM chips and should > be fixed under warranty. They just don't meet specs. Exploiting > rowhammer (as opposed to just making a machine go wrong) requires > knowing the memory mapping, and that can be facilitated by some > processor bugs. -- Len Sorensen --- Talk Mailing List [email protected] https://gtalug.org/mailman/listinfo/talk
