| Index | Recent Threads | Unanswered Threads | Who's Active | Guidelines | Search |
 |
World Community Grid Forums
Category: Support
Forum: Android Support Forum
Thread: BOINC running on all CPU-cores? |
| No member browsing this thread |
|
Thread Status: Active Total posts in this thread: 6
|
|
| Author |
|
|
_fufu
Cruncher Joined: Jun 6, 2012 Post Count: 10 Status: Offline |
I have a question about the support of ARM octa-core CPUs. Once I had a Samsung Tab S with the Exynos 5 Octa 5420 CPU. First I tought I could use all eight CPU cores for crunching. But the total amount of available cores within the BOINC preferences were four. So I thought this is because of the big.little principle those smartphone CPUs are designed. You can either use the four fast or the four slow cores, but not both at the same time.
Now I have a Huawei P8 with the Kirin 930, which is also an octa-core CPU and follows the big.little principle. But now it's possible to run BOINC at all eight cores! Is it because of a special CPU design or was there a change within the BOINC client for android and this is possible at all devices with octa-cores? |
||
|
|
SekeRob
Master Cruncher Joined: Jan 7, 2013 Post Count: 2741 Status: Offline |
No change from a client perspective since long and through latest 7.4.41. You set, after selecting "Show advanced preferences and controls", under the CPU section "Used CPU Cores". Possibly the default, not using the advanced settings, is 50%, but saw nothing in the documentation to that effect. Mostly BOINC uses 100% of cores when allowed... it's not trained to know what type of ARM chip it runs on, just that it needs to have a certain minimal code-base.
----------------------------------------Once upon a time the client listened for the 'default' profile settings on the website. That could have had a hard limit. The latest clients had that listening for the default profile settings ripped out [but am not 100% sure it really has been]. For sure, not seeing anything in the android client event log to indicate it's using website profile settings under 7.4.41. [Edit 1 times, last edit by SekeRob* at Jan 16, 2016 4:02:42 PM] |
||
|
|
SekeRob
Master Cruncher Joined: Jan 7, 2013 Post Count: 2741 Status: Offline |
BTW, just looked in the event log after a restart and it says there's a 4 core ARM, then "Using 2 CPUs", but my adv.preferences are set to use 3, and 3 are really running... Rather puzzling, something for the bug-meister were it not there's presently no Android client developer [a job opening shows on the Berkeley forums, but no one stepped up].
|
||
|
|
_fufu
Cruncher Joined: Jun 6, 2012 Post Count: 10 Status: Offline |
Thanks, SekeRob!
Just looked up the Kirin CPU at Wikipedia. Seems like the 930 and 935 are the only one without big.little, but 4+4 cores: https://en.wikipedia.org/wiki/HiSilicon You can see it in the "Microarchitecture" column. Might be the reason. Exynos has global task scheduling (GTS) which is for the same purpose, but maybe needs special programming within the app... https://en.wikipedia.org/wiki/Exynos |
||
|
|
ravenigma
Cruncher USA Joined: Oct 3, 2012 Post Count: 47 Status: Offline Project Badges: 
|
I have a couple Odroid XU4 units which have an Exynos 5422 octacore processor. They each run 8 tasks simultaneously.
---------------------------------------- |
||
|
|
_fufu
Cruncher Joined: Jun 6, 2012 Post Count: 10 Status: Offline |
Ok, good to know. Thank you!
|
||
|
|
|