Raspberry Pi Forums

tk321

I believe the theoretical peak performance of the ARM cpu is only 350Mflops double precision at 700 MHz. I'm not sure but I would guess fused multiply-add is not available on the Raspberry Pi, because its math unit is only vfpv2 and from the arm doc : The fused multiply-add instructions are only ava...

tk321

Interesting ... I can run my pi at 1 MHz now ... # echo "powersave" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor # echo 1000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq # cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq 1000 # time free total used free shared buffers ...

tk321

sdhci-bcm2708.enable_llm=1 sdhci-bcm2708.sync_after_dma=0 This seems to have no impact on the hdparm benchmark (raspbian, Kingston 8GB class 6). I get before and after something like: # hdparm -tT /dev/mmcblk0 Timing cached reads: 300 MB in 2.00 seconds = 149.87 MB/sec Timing buffered disk reads: 6...

tk321

As for armel I've only tried the official Debian squeeze release and the result is the same there. Can you execute getconf on your arm build system just to see if it's a general linux/arm issue? Dom, are you saying that the l1/l2 cache is definitely enabled despite the fact the linux kernel/libc doe...

tk321

This is probably not a raspbian issue, but getconf doesn't see the l1/l2 cache which according to http://www.raspberrypi.org/archives/1040 should be enabled. # getconf -a | grep CACHE_SIZE LEVEL1_ICACHE_SIZE 0 LEVEL1_DCACHE_SIZE 0 LEVEL2_CACHE_SIZE 0 LEVEL3_CACHE_SIZE 0 LEVEL4_CACHE_SIZE 0 Also /sys...

tk321

Yes, compilation of ffmpeg with gcc 4.6 requires > 224MB, and didn't finish in respectable time with sd-card swap disk enabled, so I gave up as well.
However, with a few patches it's possible to compile omxplayer without ffmpeg but using libav which is available in raspbian. Did you give up on this?

tk321

Any plans on getting your XBMC fork packaged into Raspbian? I know the aim of Raspbmc is to have a minimal Debian which runs XBMC but many users (me included) would like to have a more complete distribution with XBMC (gpu accelerated) as one application. Raspbian wins over Debian armel in terms of s...

tk321

I greatly appreciate the huge work done to get Raspbian build esp as it's supported by only two main developers, which I guess must be almost a full time job?! Glad to hear Debian/Raspbian is/is going to be a combined work. As per Rasbmc /XMBC, Raspbmc does not need X11 , LXDE , Scratch , tutorials ...

tk321

As far as I can see there are 3 Debian flavours : Debian: standard Debian which doesn't utilise the fpu (floating point unit) Raspbian: Debian with support for the the fpu Raspbmc: minimal Debian with gpu support for XBMC This seems to me a waste/duplication of development effort. What is the advant...

tk321

It does have cache, I believe 32k of L1 (16 + 16) and 128k of off-chip L2 that is shared with the GPU. You're right, I found some mentioning of the l2 cache but couldn't find anything on l1 cache. Still I wonder why the linux kernel can't see it, or what do you get for getconf -a | grep CACHE_SIZE ?

tk321

I've only done a quick check of its floating point performance which appears to be 350Mflops/sec peak. Instruction timings (cycles per operation) for pure register operations appear to be: fadd: 8/2 (latency/throughput) fmuld: 9/2 fdivd: 32 fsqrtd: 48 In terms of peak flop performance this is the sa...

tk321

Thanks for your great work! This is a bit off topic but do you think the debian guys would be willing to host the repository so at least you could reduce running costs and switch to a cheaper hosting package?

tk321

You guys are more experienced with github/debian packaging, so if you want to go ahead with it that'd be great. Regarding the video out problem, don't know what it could be then. My setup is pisces image changed to 192MB, connected to a monitor (hdmi-dvi) running a resolution like 1600x900 and omxpl...

tk321

Thanks for the deb package, it works perfectly for me (but can't test audio). If you get an error like "failed to open vchiq instance" you'll need to "chmod a+rw /dev/vchiq". My compile is binary compatible with your deb (md5sum: 52cbf438b0c3f51828b79d8358ef68cc omxplayer.bin) which is a good sign. ...

tk321

I can't actually add anything to that just some wishes: get some fast class 10 sd-cards working (the one I bought SanDisk Extreme Class 10 8GB just doesn't) hopefully that'd be similarly fast as an external usb stick? get X11 with native gpu acceleration, don't know if anyone is working on this and ...

tk321

Well thanks for making this project only possible! Motivated by this recent review I've also run hardinfo: hardinfo debian6 raspbian speedup CPU Blowfish 101.762 100.234 1.0 CPU CryptoHash* 8.817 8.829 1.0 CPU Fibonacci 27.018 26.663 1.0 CPU N-Queens 86.320 86.037 1.0 FPU FFT 272.413 150.656 1.8 FPU...

tk321

Thanks, it was the memory, I'm using pisces image which defaults to 224MB. I've forked omxplayer so that it natively compiles on the pi under raspbian using the libav*-dev libraries (no need to compile ffmpeg anymore). You'll need a few additional dev-packages to make it work, but I don't exactly re...

tk321

That's some good work shirro! However, do you actually get a picture? I don't: $ LD_LIBRARY_PATH=/opt/vc/lib/:../lib ./omxplayer.bin ~/mnt/test.flv * failed to open vchiq instance $ sudo chmod a+rw /dev/vchiq $ LD_LIBRARY_PATH=/opt/vc/lib/:../lib ./omxplayer.bin ~/mnt/test.flv [flv @ 0x16f8e60] Esti...

tk321

Ok, I changed a few lines in DllAvFilter.h and DllAvFilter.h and finally got it to compile with libav under raspbian. Unfortunately, omxplayer doesn't output a picture so I'm still doing something wrong, but that'll have to wait till tomorrow. DllAvUtil.h: ... extern "C" { #if (defined USE_EXTERNAL_...

tk321

Right, so you're using ffmpeg .h files but linking against libav. I'm surprised this worked out well.

tk321

That's interesting. Do you have

Code: Select all

/usr/include/libavfilter/avcodec.h

on ArchLinux and if yes which package does it belong to? If no then I'm surprised it compiled as there is

Code: Select all

omxplayer/DllAvFilter.h:55
    ...
    #include <libavfilter/avcodec.h>
    ...

tk321

I don't think it's because libav is tool old in debian6, as I get the same compiler error on raspbian (debian7): DllAvFilter.h:55:37: fatal error: libavfilter/avcodec.h: No such file or directory compilation terminated. I guess it's just because ffmpeg and libav are not identical so changes to the s...

tk321

SkG wrote: I think that the only way we can do it then is crosscompiling it then.

Or on a vm with qemu, or on the pi with swap turned on (maybe even on an external hd)...

tk321

Yes debian6/gcc-4.4.5 passes that hurdle on the pi (still gets close to the mem limit) but raspbian comes with gcc-4.6.3 which I guess uses a bit more memory and fails even on 224MB. Is there a reason why omxplayer links with ffmpeg and not libav? Could that be changed easily or involve a lot of work?

tk321

Another benchmark, this time java-script : http://www.webkit.org/perf/sunspider/sunspider.html raspbian/midori: http://www.webkit.org/perf/sunspider-0.9.1/sunspider-0.9.1/driver.html ============================================ RESULTS (means and 95% confidence intervals) ---------------------------...

Search found 31 matches

Re: MFLOP questions

Re: Overclocking

Re: SD Card performance in R-Pi onboard slot

Re: l1/l2 cache

l1/l2 cache

Re: OMXPlayer deb packages for Raspbian

Re: Raspbmc Release Candidate

Re: Combining Debian development effort

Combining Debian development effort

Re: How powerful is the CPU?

Re: How powerful is the CPU?

Re: Donations for Raspbian

Re: Omxplayer

Re: Omxplayer

Re: performance

Re: performance

Re: Omxplayer

Re: Omxplayer

Re: omxplayer - GPU enabled video player

Re: omxplayer - GPU enabled video player

Re: omxplayer - GPU enabled video player

Re: omxplayer - GPU enabled video player

Re: Omxplayer

Re: omxplayer - GPU enabled video player

Re: performance