So I got myself a new Core i7-3770K, using the stock heatsink/fan, and a motherboard that doesn’t have VCore adjustments. I re-ran a bunch of benchmarks used in my earlier posts to measure Ivy Bridge’s performance, and Hyper-threading scaling, in comparison to earlier processors. The workloads were used in the my earlier tests:
. . . → Read More: Ivy Bridge Benchmarks
There has been much speculation recently about why Intel’s new Ivy Bridge processors seem to run significantly hotter than the previous-generation Sandy Bridge processors, despite the lowered TDP rating. One proposed explanation is that the thermal interface material between the silicon die and heat spreader was changed: Sandy Bridge processors soldered the heat spreader to the silicon, while Ivy Bridge processors use some silicone-like adhesive compound. I pop off the heat spreader and do some measurements. . . . → Read More: Ivy Bridge De-lidding
A parser is used to translate wikitext to HTML for viewing. Since there are a bunch of parser projects for MediaWiki’s markup, I’ll go benchmark some of them to see how fast they run.
. . . → Read More: Mediawiki Parsers
MLPPP on Bell’s DSL GAS network doesn’t work very well because the GAS network appears to reorder PPP frames (which is forbidden by RFC 1661). Ideally, Bell should stop reordering packets. The next best option is for the ISP and user to configure MRU and MRRU settings to reduce packet/frame fragmentation. With multilink PPPoE, the client should use an IP-MTU of 1486 bytes (1484 on Linux 2.6.31+ due to a bug), a MRU of 1492, and an MRRU of 1486. The ISP should use an MRU of 1492, MRRU of 1486 (possibly 1484 to work around the Linux bug, until the bug gets fixed), and apply the IP-MTU correctly (MRU-0 = 1492 for PPP, MRU-6 = 1486 for MLPPP). . . . → Read More: Teksavvy MLPPP Performance
Intel uses Hyper-Threading (HT) as a feature for market segmentation: The desktop Core i5 processors differ from the Core i7 mainly by whether HT has been disabled, and Intel charges a significant price premium for the Core i7. Does the performance improvement of HT justify its cost? I test the performance of HT using a selection of cluster-type workloads. . . . → Read More: Hyper-Threading Performance
Process scheduling for multicore multithreaded (SMT or HT) systems adds a new challenge to an operating system’s process scheduler. Two threads scheduled on different cores will run faster than two threads scheduled onto different thread contexts of the same core because much of the hardware resources are shared between SMT thread contexts. This can be . . . → Read More: Linux SMT-Aware Process Scheduling
It has been claimed that new refrigerators use much less power than old ones. This is also the premise of The Great Refrigerator Roundup program that encourages replacement of refrigerators older than 15 years. Here is one comparison, measured over about 3 days. . . . → Read More: Refrigerator Power Efficiency
It is well-known that a car’s fuel efficiency decreases during the winter months. There are many potential contributors, including increased air density causing drag, excessively rich fuel mixture from cold starts taking a long time to warm up, increased pumping losses from dense cold air intake, increased engine oil viscosity, increased rolling friction from colder . . . → Read More: Seasonal Fuel Efficiency
See also: Ivy Bridge Benchmarks
Here are some FPGA CAD benchmarks across a few relatively-modern machines. The original motivation was to figure out why VPR ran much slower on a Core 2 Xeon 5160 system than a desktop-class Core 2 Quad Q9550. A secondary goal is to measure the Core i7-980X @ 4215 MHz. I . . . → Read More: Core 2, Nehalem, FPGA CAD
Sun claims their Sun Studio 12 compiler performs well on SPEC (Free Compiler Wins Nehalem Race by 2x). So I compared PHP 5.3.1 running PHPspeed 1.0 beta (using “Real World PHP Benchmark”) and xcache 1.3.0, compiled with Sun Studio 12, GCC 4.4.1, and Intel C Compiler 11.1.064.
System Mandriva 2010.0 x86_64 kernel 126.96.36.199-server-1mnb, Core 2 . . . → Read More: Compiler Performance