On Fri, Jun 20, 2014 at 09:39:32AM +1000, James Cameron wrote: > Therefore using an SD card instead of NAND flash should increase I/O > performance, decrease processor time, and increase available memory.
I've measured the increase in available memory. With the laptop freshly booted at the activity view and the journal icon coloured, a program is run that consumes memory in order to determine how much is available; - moving the root filesystem from NAND to SDIO is a 7% gain, from 146 MB to 156 MB, - leaving the root filesystem on NAND and adding 64 MB swap on SDIO is a 31% gain, from 146 MB to 191 MB, - moving the root filesystem from NAND to SDIO and adding 64 MB swap on SDIO is a 41% gain, from 146 MB to 206 MB. A visualisation of the results: https://plot.ly/~quozl/7/xo-1-256-mb-usable-memory-1321-nand-vs-sdio-as-root/ The test program: http://dev.laptop.org/~quozl/z/1WyA0M.txt (oom.c) Measurement was the anon-rss in the kernel OOM message, e.g. [ 761.307460] Killed process 937 (oom) total-vm:197692kB, anon-rss:183048kB, file-rss:4kB -- James Cameron http://quozl.linux.org.au/ _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel