dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5372
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Location: Cambridge

Re: Overclocking

Mon Sep 24, 2012 2:49 pm

kevs3d wrote:I'm using forceturbo so I assume that won't matter? I also have a Kingston class 4 card with an identical image that I'm about to see if i can reproduce the issue on - i'm testing up to arm1100 ovolt8 with that also.

Is there anything that can be one to "tame" the class 10 cards if it does prove to be the problem...?
If the bogmips/delay is the problem, then forceturbo will avoid it. If it is something else, then you will have to experiment.

Obviously back up, or use a disposable image when testing. My guess is you won't see corruption (this overclock thread has gone on months without corruption being a significant problem).
But if, you do, try winding back the settings (arm_freq, core_freq, sdram_freq and over_coltage) and identify which one seems to cause to the corruption.

kevs3d
Posts: 23
Joined: Fri Sep 07, 2012 6:26 pm

Re: Overclocking

Mon Sep 24, 2012 4:07 pm

dom wrote:
kevs3d wrote:I'm using forceturbo so I assume that won't matter? I also have a Kingston class 4 card with an identical image that I'm about to see if i can reproduce the issue on - i'm testing up to arm1100 ovolt8 with that also.

Is there anything that can be one to "tame" the class 10 cards if it does prove to be the problem...?
If the bogmips/delay is the problem, then forceturbo will avoid it. If it is something else, then you will have to experiment.

Obviously back up, or use a disposable image when testing. My guess is you won't see corruption (this overclock thread has gone on months without corruption being a significant problem).
But if, you do, try winding back the settings (arm_freq, core_freq, sdram_freq and over_coltage) and identify which one seems to cause to the corruption.
Yep i've got backups and several cards to play with.

Been experimenting with the class4 card. I cannot corrupt it - even with arm1100, core500, ov8. The class10 card gets into a mess within a few writes - every time. The 1100mhz overclock is rock solid in quake3 and cpu tests and card writes with the class4 card. So i guess this is pointing to card compatibility when overclocked. To be specific the card is a Transcend 8gb class 10 TS8GSDHC10. I have no trouble with it when clocked at around 850mhz or lower with no overvolt used.

So do you think this means the card just isn't going to fly at overclocked speeds or is there potentially some magic you can do...? Thanks again for all you hard work on this and the overclocking firmware which i'm loving playing with!!

Kev
--
http://www.kevs3d.co.uk/dev - HTML5 canvas games, demos and utils.

Tobor
Posts: 7
Joined: Thu Aug 16, 2012 6:42 am

Re: Overclocking

Mon Sep 24, 2012 4:20 pm

FWIW, I was hit by this problem while using force_turbo=1, triggered by doing apt-get update & upgrade, could also reproduce (but just once) by reading & writing a 100MB file with dd. Having rolled back to a backup image I made on 20th everything works OK (>24h uptime) with the exact same settings.

Overclock:

Code: Select all

arm_freq=1100

sdram_freq=600

core_freq=500
avoid_pwm_pll=1
gpu_freq=290

over_voltage=8
current_limit_override=0x5A000020

force_turbo=1
Version info from the "old" image I'm using now:

Code: Select all

[email protected] ~ $ /opt/vc/bin/vcgencmd version
Sep 16 2012 14:37:55 
Copyright (c) 2012 Broadcom
version 337302 (release)
[email protected] ~ $ uname -a
Linux raspberrypi 3.2.27+ #151 PREEMPT Fri Sep 14 17:00:51 BST 2012 armv6l GNU/Linux
Maybe not related but 9 times out of 10 during boot I get:

Code: Select all

[    2.133655] mmc0: problem reading SD Status register.
regardless of whether I overclock or not, with both of my SD-cards (A-DATA Class 10 and no-name Class 6).

dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5372
Joined: Wed Aug 17, 2011 7:41 pm
Location: Cambridge

Re: Overclocking

Mon Sep 24, 2012 4:23 pm

kevs3d wrote: Yep i've got backups and several cards to play with.

Been experimenting with the class4 card. I cannot corrupt it - even with arm1100, core500, ov8. The class10 card gets into a mess within a few writes - every time. The 1100mhz overclock is rock solid in quake3 and cpu tests and card writes with the class4 card. So i guess this is pointing to card compatibility when overclocked. To be specific the card is a Transcend 8gb class 10 TS8GSDHC10. I have no trouble with it when clocked at around 850mhz or lower with no overvolt used.

So do you think this means the card just isn't going to fly at overclocked speeds or is there potentially some magic you can do...? Thanks again for all you hard work on this and the overclocking firmware which i'm loving playing with!!

Kev
First test it to follow this:
http://www.raspberrypi.org/phpBB3/viewt ... 25#p180099

Does it fix the class 10 card?

davecochran
Posts: 5
Joined: Wed Sep 19, 2012 1:06 am
Location: Louisiana

Re: Overclocking

Mon Sep 24, 2012 5:13 pm

Using a Transcend 64G Class 10 card here... So far no corruption regardless of the clock speed etc...perhaps being at the top of the capacity scale thus newer the cards are improved?

I've got some older and some REALLY old 4G and smaller cards laying around somewhere. I'll try them this evening.

kevs3d
Posts: 23
Joined: Fri Sep 07, 2012 6:26 pm

Re: Overclocking

Mon Sep 24, 2012 6:03 pm

OK I'm giving it a bash (hah) now with the setting you suggested and it's MUCH better! So far no corruption!! Again up to arm1100,core500,dram450,ov8 - so right at the max settings I appear to be able to get away with.

Thanks

Kev
--
http://www.kevs3d.co.uk/dev - HTML5 canvas games, demos and utils.

dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5372
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Location: Cambridge

Re: Overclocking

Mon Sep 24, 2012 6:11 pm

kevs3d wrote:OK I'm giving it a bash (hah) now with the setting you suggested and it's MUCH better! So far no corruption!! Again up to arm1100,core500,dram450,ov8 - so right at the max settings I appear to be able to get away with.
Good to hear. I'll try to fix the BogoMips/udelay problem in the kernel, using the system timer as a fixed way of measuring delay.

kevs3d
Posts: 23
Joined: Fri Sep 07, 2012 6:26 pm

Re: Overclocking

Mon Sep 24, 2012 7:59 pm

FYI i was still able to eventually corrupt the FAT partition doing rpi-update (it managed to get through an apt-get update+upgrade no trouble first, so much better certainly) but it's not quite there yet i think.

Errors i see on boot randomly:

mmc:0 missed completion of cmd 18 DMA (512/512 [1][1]) - ignoring it

Hope that helps,

Kev
--
http://www.kevs3d.co.uk/dev - HTML5 canvas games, demos and utils.

dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5372
Joined: Wed Aug 17, 2011 7:41 pm
Location: Cambridge

Re: Overclocking

Mon Sep 24, 2012 8:17 pm

kevs3d wrote:mmc:0 missed completion of cmd 18 DMA (512/512 [1][1]) - ignoring it
I've had that since day one. I've been told it is harmless. We should probably suppress the message.

User avatar
hojnikb
Posts: 128
Joined: Mon Jun 04, 2012 3:59 pm
Location: @Home

Re: Overclocking

Mon Sep 24, 2012 9:08 pm

dom wrote:
kevs3d wrote:mmc:0 missed completion of cmd 18 DMA (512/512 [1][1]) - ignoring it
I've had that since day one. I've been told it is harmless. We should probably suppress the message.
I've got these aswell. Good to know they are harmless.. :D
+°´°+,¸¸,+°´°~ Everyone should have a taste of UK Raspberry Pie =D ~°´°+,¸¸,+°´°+
Rasberry Pi, SoC @ 1225Mhz :o, 256MB Ram @ 550Mhz, 16GB SD-Card, Raspbian

portets
Posts: 186
Joined: Sat Oct 29, 2011 6:24 am

Re: Overclocking

Mon Sep 24, 2012 9:28 pm

In addition to:

Code: Select all

[   10.878268] EXT4-fs (mmcblk0p2): re-mounted. Opts: (null)
[   11.403159] EXT4-fs (mmcblk0p2): re-mounted. Opts: (null)
[   16.462634] mmc0: missed completion of cmd 18 DMA (512/512 [1]/[1]) - ignoring it
I also get:

Code: Select all

[   16.478712] mmc0: DMA IRQ 6 ignored - results were reset
About 1 out of every 6 boots. On two different sd cards. Is this also normal?

kevs3d
Posts: 23
Joined: Fri Sep 07, 2012 6:26 pm

Re: Overclocking

Mon Sep 24, 2012 10:23 pm

portets wrote:In addition to:

Code: Select all

[   10.878268] EXT4-fs (mmcblk0p2): re-mounted. Opts: (null)
[   11.403159] EXT4-fs (mmcblk0p2): re-mounted. Opts: (null)
[   16.462634] mmc0: missed completion of cmd 18 DMA (512/512 [1]/[1]) - ignoring it
I also get:

Code: Select all

[   16.478712] mmc0: DMA IRQ 6 ignored - results were reset
About 1 out of every 6 boots. On two different sd cards. Is this also normal?
I see those msgs quite often also, are they all safe to ignore...?
--
http://www.kevs3d.co.uk/dev - HTML5 canvas games, demos and utils.

kevs3d
Posts: 23
Joined: Fri Sep 07, 2012 6:26 pm

Re: Overclocking

Tue Sep 25, 2012 8:55 am

kevs3d wrote:FYI i was still able to eventually corrupt the FAT partition doing rpi-update (it managed to get through an apt-get update+upgrade no trouble first, so much better certainly) but it's not quite there yet i think.

Errors i see on boot randomly:

mmc:0 missed completion of cmd 18 DMA (512/512 [1][1]) - ignoring it

Hope that helps,

Kev
If there's any other settings I can try or other suggestions I'll give them a go...? I will spend some time this evening seeing I can I identify which overclocked setting that makes it more likely to corrupt the card i.e. arm/core/volts.
--
http://www.kevs3d.co.uk/dev - HTML5 canvas games, demos and utils.

dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5372
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Location: Cambridge

Re: Overclocking

Tue Sep 25, 2012 9:09 am

kevs3d wrote: If there's any other settings I can try or other suggestions I'll give them a go...? I will spend some time this evening seeing I can I identify which overclocked setting that makes it more likely to corrupt the card i.e. arm/core/volts.
I've committed a kernel fix to use the system timer for udelay, so the initial_turbo setting shouldn't be needed.
So, update first, and investigate which of the overclock settings seem to corrupt the card.

Atrox2201
Posts: 7
Joined: Fri Sep 21, 2012 9:13 pm

Re: Overclocking

Tue Sep 25, 2012 10:54 am

I'm not sure if my OC settings are taking effect.

If I run vcgencmd it still shows stock clocks?

kevs3d
Posts: 23
Joined: Fri Sep 07, 2012 6:26 pm

Re: Overclocking

Tue Sep 25, 2012 11:12 am

dom wrote:
kevs3d wrote: If there's any other settings I can try or other suggestions I'll give them a go...? I will spend some time this evening seeing I can I identify which overclocked setting that makes it more likely to corrupt the card i.e. arm/core/volts.
I've committed a kernel fix to use the system timer for udelay, so the initial_turbo setting shouldn't be needed.
So, update first, and investigate which of the overclock settings seem to corrupt the card.
OK will do.

Kev
--
http://www.kevs3d.co.uk/dev - HTML5 canvas games, demos and utils.

papermonster
Posts: 1
Joined: Tue Sep 25, 2012 1:36 pm

Re: Overclocking

Tue Sep 25, 2012 2:04 pm

Atrox2201 wrote:I'm not sure if my OC settings are taking effect.

If I run vcgencmd it still shows stock clocks?
i've the some problem. Overclock done by raspi-config to 1Ghz.
when i check in config.txt, every arm parameter is overclocked, but with vcgencmd everything is standard.
i'm using the lastest raspbian image, and it is visible quicker then the previous, but i would like to check the arm speeds.
i'm using a 5V 700mA power supply,could this be the bottleneck?

Dilligaf
Posts: 283
Joined: Wed May 23, 2012 6:48 pm

Re: Overclocking

Tue Sep 25, 2012 3:27 pm

dom wrote:
kevs3d wrote: If there's any other settings I can try or other suggestions I'll give them a go...? I will spend some time this evening seeing I can I identify which overclocked setting that makes it more likely to corrupt the card i.e. arm/core/volts.
I've committed a kernel fix to use the system timer for udelay, so the initial_turbo setting shouldn't be needed.
So, update first, and investigate which of the overclock settings seem to corrupt the card.
Does this fix require the whole kernel or still just the start.elf?

dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5372
Joined: Wed Aug 17, 2011 7:41 pm
Location: Cambridge

Re: Overclocking

Tue Sep 25, 2012 3:37 pm

papermonster wrote:
Atrox2201 wrote:I'm not sure if my OC settings are taking effect.

If I run vcgencmd it still shows stock clocks?
i've the some problem. Overclock done by raspi-config to 1Ghz.
when i check in config.txt, every arm parameter is overclocked, but with vcgencmd everything is standard.
i'm using the lastest raspbian image, and it is visible quicker then the previous, but i would like to check the arm speeds.
i'm using a 5V 700mA power supply,could this be the bottleneck?
It's a dynamic overclock. The frequency only increses when busy. Try launching X, and in a terminal measure the clocks while midori or scratch is busy.

dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5372
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Location: Cambridge

Re: Overclocking

Tue Sep 25, 2012 3:38 pm

Dilligaf wrote:
dom wrote:
kevs3d wrote: If there's any other settings I can try or other suggestions I'll give them a go...? I will spend some time this evening seeing I can I identify which overclocked setting that makes it more likely to corrupt the card i.e. arm/core/volts.
I've committed a kernel fix to use the system timer for udelay, so the initial_turbo setting shouldn't be needed.
So, update first, and investigate which of the overclock settings seem to corrupt the card.
Does this fix require the whole kernel or still just the start.elf?
This is a kernel fix.

Dilligaf
Posts: 283
Joined: Wed May 23, 2012 6:48 pm

Re: Overclocking

Tue Sep 25, 2012 7:01 pm

Just built and booted the new kernel, does this look right? BogoMIPS seems awfully low

[email protected]:~# cat /proc/cpuinfo
Processor : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS : 464.48
Features : swp half thumb fastmult vfp edsp java tls
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x0
CPU part : 0xb76
CPU revision : 7

Hardware : BCM2708
Revision : 1000002

[email protected]:~# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
900000

milhouse
Posts: 641
Joined: Mon Jan 16, 2012 12:59 pm

Re: Overclocking

Tue Sep 25, 2012 7:34 pm

I've written a simple command-line overclock monitoring script if anyone is interested - I normally put it on the /boot partition for safe keeping/easy access:

wget http://www.nmacleod.com/public/bcmstat.sh

Code: Select all

[email protected] ~ $ /boot/bcmstat.sh
Governor: ondemand
Min Freq:  700Mhz
Max Freq: 1000Mhz
 Version: Sep 23 2012 14:54:04, version 338882 (release)
vcg path: /usr/bin/vcgencmd

Time          ARM     Core     h264  Core Temp (Max)   Core  SDRam  IRQ/s
========  =======  =======  =======  ===============  =====  =====  =====
20:13:44   700Mhz   250Mhz   250Mhz  50.84C (50.84C)  1.20V  1.20V   1098
20:13:46   700Mhz   250Mhz   250Mhz  49.77C (50.84C)  1.20V  1.20V    795
20:13:49  1000Mhz   500Mhz   250Mhz  51.92C (51.92C)  1.35V  1.30V    837
20:13:51  1000Mhz   500Mhz   250Mhz  51.92C (51.92C)  1.35V  1.30V    809
20:13:53  1000Mhz   500Mhz   250Mhz  52.46C (52.46C)  1.35V  1.30V    854
20:13:55   700Mhz   250Mhz   250Mhz  51.38C (52.46C)  1.20V  1.20V    852
20:13:57   700Mhz   250Mhz   250Mhz  50.84C (52.46C)  1.20V  1.20V    831
^C
You can specify the loop interval in seconds (eg. /boot/bcmstat 5 for every 5 seconds). Default is every 2 seconds.

It's also quite handy if you're interested to know how hot your Pi gets during an extended test run.

Also for monitoring network activity:

wget http://www.nmacleod.com/public/netmon.sh

Code: Select all

[email protected] ~ $ /boot/netmon.sh
Time      RX bytes/s  TX bytes/s
========  ==========  ==========
20:17:56         234         498
20:17:57         147         328
20:17:59       1,201         402
20:18:00         147         329
^C
Again, you can specify a loop interval - default is every 1 second. Works with eth0 as standard, specify interval AND interface as parameters to override eg. (/boot/netmon.sh 1 br1).

Both scripts tested with Raspbian and OpeELEC.
Raspbian requires gawk (sudo apt-get install gawk) for netmon.sh.

Dilligaf
Posts: 283
Joined: Wed May 23, 2012 6:48 pm

Re: Overclocking

Tue Sep 25, 2012 7:41 pm

Just initiated a library scan in XBMC with the new kernel at 900/450/450 and I ended up with a corrupted file system, so it's not a fix.

chochis
Posts: 14
Joined: Mon Jul 16, 2012 8:29 pm

Re: Overclocking

Wed Sep 26, 2012 12:57 am

I also ended up with a corrupted partition.

First put to the top turbo settings and with the xbmc my raspi died a couple of time so I decided to put a step lower, then, it started to behave poorer, not even answering to ssh and after a reboot all was corrupted :-(

Dilligaf
Posts: 283
Joined: Wed May 23, 2012 6:48 pm

Re: Overclocking

Wed Sep 26, 2012 12:59 am

I did it again, this time at 850/375/375. Settings that were stable before the dynamic OC

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