Am 05.07.2014 19:59, schrieb Jason Smith: > I am trying to build a cross compiler on a BeagleBone Black to compile > from ARM to x86. The intent of this is to use the low power consuming > BeagleBone Black that I had on hand as a build server. It can already > compile for windows through mingw-w64, but I need it to also compile the > code for Linux x86 systems. Hi Jason, do you have measured power consumption of an x86 based-system and compared it to the power consumption of your BeagleBone? I have measured the power consumption using Fritzbox 7390 and Fritz Dect 200, thus its the consumption of the complete system. We have a ARM-based quad-core Utilite Pro (http://utilite-computer.com/) (Freescale i.MX6 quad-core Cortex-A9 @1GHz running ubunutu 12.04) system consuming around 5 Watt in idle mode and around 8 Watt average when 3 cores are active. Our quad-core Xeon x86 64-bit (Xeon(R) CPU E3-1245 v3 @ 3.40GHz, limited to 2.9GHz running debian 7.5) system uses 20 Watt in idle and around 40 Watt average when 3 cores are active. An build of our MyARM software needs 5 minutes on the xeon-system (building totally in RAM ;-) and 19 minutes on the ARM-based system. Now roughly calculating power consumption: Xeon-based: 40W * ( 5/60)h = ~3.3Wh ARM-based: 8W * (19/60)h = ~2.5Wh Now measuring build time and power consumption when only a single core is used: Xeon-based: 11.5 minutes build time and around 34 Watt average ARM-based 40.5 minutes build time and around 7 Watt average Resulting in the following power consumption: Xeon-based: 34W * (11,5/60)h = ~6.5Wh ARM-based: 7W * (40,5/60)h = ~4.7Wh With 4 cores active: Xeon-based: 44W * (4,25/60)h = ~3,11Wh ARM-based: 9W * (17/60)h = ~2,55Wh Thus using more cores reduces overall power consumption and our ARM-based system uses around 30% less power. But our Xeon-Server is a VM-Server serving up-to 18 different VMs with different operating systems... Regards, Stefan -- MyARM measuring response time, performance and more ...
