Changes between Version 1 and Version 2 of BOINConPhones

Timestamp:

Jan 31, 2012, 1:37:01 PM (12 years ago)

Author:

jbk

Comment:

--

BOINConPhones

@@ -24 +24 @@
 There is no long term impact on the phone itself from running BOINC. The on-chip cooling (at least when running CPU-only mode science apps) is more than capable of keeping the CPU cool so that there is no damage done to it. Also most smart-phones are deliberately under-clocked to further decrease heat.
 
-The battery, however, may sustain long term damage from the overall heat increase (however small it is). There are different models for each battery type but the general idea is that the higher the temperature the faster the internal structure in the battery will deteriorate. When the internal structure of the battery degrades the battery slowly loses the ability to gain maximal charge. For Li-Ion batteries this process happens even when the battery is on the store shelf at 20 degrees Celsius. Quoted battery shelf deterioation is typically as high as 20% per year of permanent maximal charge loss^(see [#notes note]).
+The battery, however, may sustain long term damage from the overall heat increase (however small it is). There are different models for each battery type but the general idea is that the higher the temperature and the higher the average charge state the faster the internal structure in the battery will deteriorate. When the internal structure of the battery degrades the battery slowly loses the ability to gain maximal charge. For Li-Ion batteries this process happens even when the battery is on the store shelf at 20 degrees Celsius. Quoted battery shelf deterioration for a fully charged battery is typically as high as 20% per year of permanent maximal charge loss^(see [#notes note]).
+Due to the fact that battery longevity is also coupled to the maximal discharge depth in each charge-discharge cycle - and that BOINC will potentially make this discharge deeper - it is difficult to assess exactly what the impact will be without getting some real-world feedback. 
 
 
 == Performance ==
+
+As a small and embedded system the smart phone CPU and memory systems will typically trail behind desktop and laptop machines by an order of magnitude. It is easily possible for a single modern GPU to out-perform a smartphone (CPU-only mode) by a factor 100 or more.
+In a test with a HTC Desire Android phone the phone used more than 2 days to complete what the GPU completed in less than 1 hour. On the other hand, smartphones are almost always left powered on 24/7 whereas GPUs are only turned on when the computer is running. It is likely that smartphones could provide a considerable computational contribution from their sheer volume and the fact that they are kept always on.
+This section talks a bit about limitations on phones as seen from BOINC or a science application.
+
 === Limitations ===
-memory
+
+TODO: Write out this section
+
+* memory
+* 1) typically no swap
+* 2) kernel memory killer
+* 3) Shared memory structures + mmap (BOINC >=6)
+
+* Internet access
+* 1) internet costs power (and potentially money)
+* 2) Access control
+
+* Storage
+* 1) yaffs and related issues + how to solve them with BOINC settings
+
+
+=== Libraries with NEON support ===
+
+The FFTW3.3.1 beta introduces neon support for FFT. Configure with --enable-neon and a neon-compatible architecture set to activate it during compilation. If you do a wisdom file it will now show the neon codelets as being the fastest ones.
+
 
 == Tested Devices ==
 
-== Dump ==
->6
+This section has a list of tested phones, their capabilities and suggested compile flags for native components:
+||                                                                  ||= SoC/CPU                  =||= Speed (from cpuinfo) =||= Memory                             =||= Flags =||= Comments =||
+|| [http://en.wikipedia.org/wiki/HTC_Desire HTC Desire (Bravo)]     || ARMv7 SnapDragon QSD8250   || 738.83 BogoMips        || 576MB (412MB available for BOINC)    || "-march=armv7-a -mfpu=vfpv3 -mfloat-abi=hard" or "-march=armv7-a -mfpu=neon -mfloat-abi=hard" || Tested with Cyanogenmod 2.6.37.6 kernel. Requires BOINC API >= 6.x ||
+
+
+== Actually Running BOINC ==
+
+TODO: Write out this section
+* Installation instructions for Android
+
+* Phone friendly managers
 
 == Notes ==