LinHES Forums
http://forum.linhes.org/

TFW, Error: Write() -- IOBOUND begin cnt Errors
http://forum.linhes.org/viewtopic.php?f=6&t=16904		 Page 1 of 1
Author:  mihanson [ Mon Oct 08, 2007 2:32 pm ]
Post subject:  TFW, Error: Write() -- IOBOUND begin cnt Errors
Last Thursday night I saw some errors on my backend machine that caused a small portion of some shows that I was recording to be lost. I have 3 OTA HD tuners and a PVR-150 in the backend. At the time, Survivor, Ugly Betty and 30 Rock were all recording on the OTA HD tuners and the PVR-150 was free. My wife was time shifting Ugly Betty on rfe-1. No commflagging or mythfilldatabase was running, but I do run folding@home on this backend. The lines below about buffers being overflowed tells me that the backend could not keep up with the demand, but I was wondering if anyone else has seen this and found a solution. I've seen posts about the IOBOUND errors, but they seem to be linked to mythfilldatabase. My complete specs are linked in my signature. Thanks.

Quote:
2007-10-04 20:17:45.146 adding: mythbox-rfe-1 as a client (events: 0)
2007-10-04 20:29:31.529 TVRec(3): Changing from None to RecordingOnly
2007-10-04 20:29:31.550 TVRec(3): HW Tuner: 3->3
2007-10-04 20:29:31.885 Started recording: 30 Rock "Seinfeld Vision": channel 1041 on cardid 3, sourceid 1
2007-10-04 20:42:23.942 Expiring MLB Baseball "American League Division Series, Game 1: Teams TBA" from Wed Oct 3 17:30:00 2007, 605 MBytes, forced expire (LiveTV record$
2007-10-04 20:46:50.071 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(3407)
2007-10-04 20:46:50.238 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(4159)
2007-10-04 20:46:51.093 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(7919)
2007-10-04 20:50:03.872 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:03.877 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:03.881 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(7919)
2007-10-04 20:50:03.872 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:03.884 DevRdB(2) Error: Driver buffers overflowed
2007-10-04 20:50:03.900 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(3783)
2007-10-04 20:50:03.905 DevRdB(0) Error: Driver buffers overflowed
2007-10-04 20:50:03.905 DevRdB(1) Error: Driver buffers overflowed
2007-10-04 20:50:03.922 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(4259)
2007-10-04 20:50:03.938 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:03.981 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.025 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.046 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(6703)
2007-10-04 20:50:04.053 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(9159)
2007-10-04 20:50:04.138 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.213 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.261 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(2391)
2007-10-04 20:50:04.319 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(2567)
2007-10-04 20:50:04.325 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(7303)
2007-10-04 20:50:04.371 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.372 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.381 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.389 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(8363)
2007-10-04 20:50:04.393 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(3839)
2007-10-04 20:50:04.418 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.466 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.475 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(7191)
2007-10-04 20:50:04.498 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(4083)
2007-10-04 20:50:04.554 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.554 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.644 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(7159)
2007-10-04 20:50:04.687 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.744 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(5103)
2007-10-04 20:50:04.785 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.799 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(1299)
2007-10-04 20:50:04.807 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.818 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(530055)
2007-10-04 20:50:04.825 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.918 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(95)
2007-10-04 20:50:04.935 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:04.958 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(7151)
2007-10-04 20:50:04.961 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(2523)
2007-10-04 20:50:04.971 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.064 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(6979)
2007-10-04 20:50:05.065 TFW, Error: Write() -- IOBOUND begin cnt(10152) free(455)
2007-10-04 20:50:05.102 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.133 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.152 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.155 TFW, Error: Write() -- IOBOUND begin cnt(9588) free(8755)
2007-10-04 20:50:05.189 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.277 TFW, Error: Write() -- IOBOUND begin cnt(188) free(175)
2007-10-04 20:50:05.291 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.330 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(6623)
2007-10-04 20:50:05.492 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.548 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(8515)
2007-10-04 20:50:05.599 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(5255)
2007-10-04 20:50:05.601 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(2047)
2007-10-04 20:50:05.652 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.722 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.722 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.724 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.738 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(4711)
2007-10-04 20:50:05.763 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(5487)
2007-10-04 20:50:05.805 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(8939)
2007-10-04 20:50:05.818 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.832 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(3255)
2007-10-04 20:50:05.842 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.843 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.883 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(1051)
2007-10-04 20:50:05.903 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:05.919 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(2847)
2007-10-04 20:50:05.967 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:06.043 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:06.143 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(2291)
2007-10-04 20:50:06.161 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:06.190 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(4459)
2007-10-04 20:50:06.387 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:06.412 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(6815)
2007-10-04 20:50:06.454 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:06.472 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(1131)
2007-10-04 20:50:06.482 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:06.492 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(7479)
2007-10-04 20:50:06.549 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:06.941 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(2347)
2007-10-04 20:50:06.962 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:06.975 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(8507)
2007-10-04 20:50:06.979 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:07.042 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(4671)
2007-10-04 20:50:07.133 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:07.147 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(491)
2007-10-04 20:50:07.154 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:07.165 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(2703)
2007-10-04 20:50:07.173 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:07.183 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(8675)
2007-10-04 20:50:07.187 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:07.199 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(8067)
2007-10-04 20:50:07.206 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:07.217 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(4075)
2007-10-04 20:50:07.225 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:07.235 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(1963)
2007-10-04 20:50:07.242 TFW, Error: Write() -- IOBOUND end
2007-10-04 20:50:07.251 TFW, Error: Write() -- IOBOUND begin cnt(9400) free(6243)
2007-10-04 20:50:07.260 TFW, Error: Write() -- IOBOUND end
2007-10-04 21:00:02.492 TVRec(2): Changing from RecordingOnly to None
2007-10-04 21:00:02.543 Finished recording Survivor: China "I Lost Two Hands and Possibly a Shoulder!": channel 1021
2007-10-04 21:00:02.747 Finished recording Survivor: China "I Lost Two Hands and Possibly a Shoulder!": channel 1021
2007-10-04 21:00:03.122 TVRec(2): Changing from None to RecordingOnly
2007-10-04 21:00:03.129 TVRec(2): HW Tuner: 2->2
2007-10-04 21:00:03.435 Started recording: The Office "Dunder-Mifflin Infinity": channel 1041 on cardid 2, sourceid 1
2007-10-04 21:00:03.615 TVRec(1): Changing from RecordingOnly to None
2007-10-04 21:00:03.631 Finished recording Ugly Betty "Family/Affair": channel 1071
2007-10-04 21:00:04.052 Finished recording Ugly Betty "Family/Affair": channel 1071
2007-10-04 21:00:04.191 TVRec(1): Changing from None to RecordingOnly
2007-10-04 21:00:04.198 TVRec(1): HW Tuner: 1->1
0: start_time: 3863.208 duration: 326.767
1: start_time: 3863.189 duration: 326.753
stream: start_time: 42924.324 duration: 3630.957 bitrate=11424 kb/s
2007-10-04 21:00:04.208 AFD: Opened codec 0x82fc470, id(MPEG2VIDEO) type(Video)
2007-10-04 21:00:04.211 AFD: Opened codec 0x832f160, id(AC3) type(Audio)
2007-10-04 21:00:04.593 Started recording: Grey's Anatomy "Love/Addiction": channel 1071 on cardid 1, sourceid 1
Author:  slowtolearn [ Mon Oct 08, 2007 3:26 pm ]
Post subject: 
Network issues or slow/problematic disk(s)? Perhaps some files were being deleted at the time? http://www.mythtv.org/wiki/index.php/Op ... erformance
Author:  mihanson [ Mon Oct 08, 2007 6:47 pm ]
Post subject: 
Disks are SATA/300 jumpered to run at 150MB/s (because that's what the motherboard supports). Nothing else other than recording and 1 frontend viewing was occuring at the time. I had most of the NFS options (no MS Windows on the network) mentioned in the referenced link above already implemented, but I did not have the nfsvers=3 option on all my boxen so I added them and remounted the /myth directory. We'll see if that helps. There is a link to PCI latency in the aboive mentioned thread that I found interesting. I cannot seem to get the IDE/SATA controllers to take a value. I'll have to look into the BIOS for it.
Author:  mihanson [ Mon Oct 08, 2007 11:11 pm ]
Post subject: 
Had a chance to check the BIOS settings out. Nothing in there allowed me to change IRQ assignments above IRQ 15 (where all my PCI cards are). I disabled ACPI and APIC, reset ECSD. I still cannot figure out how to change the latency settings of my IDE/SATA controller like that of the example in the link slowtolearn posted above. I'll report back any improvement/worsening/revalations later.
Author:  rando [ Tue Oct 09, 2007 6:27 am ]
Post subject: 
mihanson wrote:
Had a chance to check the BIOS settings out. Nothing in there allowed me to change IRQ assignments above IRQ 15 (where all my PCI cards are). I disabled ACPI and APIC, reset ECSD. I still cannot figure out how to change the latency settings of my IDE/SATA controller like that of the example in the link slowtolearn posted above. I'll report back any improvement/worsening/revalations later.



I've had motherboards where I was unable to change the latency
. I'm not sure if you've read this section of the Myth Wiki (it's linked from the url posted above).

http://www.mythtv.org/wiki/index.php/Talk:PCI_Latency

I am also sitting in a situation where I cannot adjust the PCI Latency, it's simply stuck at zero, and I'm sure that's the root of the IOBOUND errors I've been seeing for several months now (on two different motherboards). My suggestion is to increase the buffers for your IVTV mpg buffers.

http://www.knoppmythwiki.org/index.php? ... imizeHowTo

I don't know if you've read this page, but it'd be a good place to start (or rather to continue) your troubleshooting.
Author:  marc.aronson [ Tue Oct 09, 2007 6:57 am ]
Post subject: 
Quote:
I've seen posts about the IOBOUND errors, but they seem to be linked to mythfilldatabase. My complete specs are linked in my signature


mythfilldatabase is only one of many reasons that this can occur. The scheduler runs every time a new recording is about to start and can trigger a fair amount of database activity. I suggest you try the following steps from the article http://www.knoppmythwiki.org/index.php? ... imizeHowTo

1. Optimize database

2. Reduce the volume of program guide data

3. Increase buffer size for IVTV

Are you running any "watchdog" / "baby sitting" scripts that autodetect a hung backend? If so, see also "Fixing problematic watchdog scripts".

In addiiton, select the "delete files slowly" option in your setup. Deleting an HD file can take a lot of I/O if you're using EXT3. I found it helpful even though I use XFS, which is efficient at large file deletes.

Marc
Author:  mihanson [ Tue Oct 09, 2007 7:46 am ]
Post subject: 
rando wrote:
I've had motherboards where I was unable to change the latency
. I'm not sure if you've read this section of the Myth Wiki (it's linked from the url posted above).

http://www.mythtv.org/wiki/index.php/Talk:PCI_Latency

Yes, that's the article on PCI latency I was referring to above.

rando wrote:
My suggestion is to increase the buffers for your IVTV mpg buffers.

http://www.knoppmythwiki.org/index.php? ... imizeHowTo


Yes, I did increase IVTV buffers a while back althought my IVTV card (PVR-150) was not in use when the errors I quotes in my OP occurred. Thank you for the suggestions.

marc.aronson wrote:
mythfilldatabase is only one of many reasons that this can occur. The scheduler runs every time a new recording is about to start and can trigger a fair amount of database activity. I suggest you try the following steps from the article http://www.knoppmythwiki.org/index.php? ... imizeHowTo

1. Optimize database


This is done nightly before my backup runs.

Quote:
2. Reduce the volume of program guide data

I'll give it a shot.

Quote:
3. Increase buffer size for IVTV

Done already.

Quote:
Are you running any "watchdog" / "baby sitting" scripts that autodetect a hung backend? If so, see also "Fixing problematic watchdog scripts".

I am renicing commflaggin from my .fluxbox/apps startup programs. I just killed this script and set it back up as a crontab job running twice per hour (at 03,33). We'll see if that helps.

Quote:
In addiiton, select the "delete files slowly" option in your setup. Deleting an HD file can take a lot of I/O if you're using EXT3. I found it helpful even though I use XFS, which is efficient at large file deletes.

I'll try this too. Thank you.
Author:  marc.aronson [ Thu Oct 25, 2007 11:40 pm ]
Post subject: 
After upgrading from R5D1 to R5F27 I started to have IOBOUND problems again. I applied the following additional tweaks from http://www.mythtv.org/wiki/index.php/Op ... erformance and my problems have gone away:

1. Enabled fast writes in the Nvidia driver.

2. Enabled async mode in NFS.

3. Increased the default allocation size in the XFS file system to reduce fragmentation. The article suggests increasing the default allocation size to 512m, but I only increased it to 512k so as to avoid wasting too much disk space with smaller files.

4. Modifed the mysql settings as suggested. Note: Only make the subset of changes that increase buffer/cache sizes.

Marc
Author:  mihanson [ Fri Oct 26, 2007 10:59 am ]
Post subject: 
marc.aronson wrote:
After upgrading from R5D1 to R5F27 I started to have IOBOUND problems again. I applied the following additional tweaks from http://www.mythtv.org/wiki/index.php/Op ... erformance and my problems have gone away:

1. Enabled fast writes in the Nvidia driver.


Marc,
Can you provide more detail on the above procedure? The page linked to from the Mythtv page Re: Fast writes is a gentoo based page. Paths and file names are different in Debian/Knoppmyth. I believe I could figure it out if I had enough time to muck around, but I don't want to hose my install. Enlighten us, please. :D
Author:  marc.aronson [ Fri Oct 26, 2007 5:20 pm ]
Post subject: 
To enable fast writes in the Nvidia driver on R5F27 add the following line to the end of /etc/modprobe.d/nvidia-kernel-nkc:

Code:
options nvidia NVreg_EnableAGPFW=1


Additional details on how to apply the tweaks to R5F27 can be found at http://www.knoppmythwiki.org/index.php? ... imizeHowTo in the section titled "Check out the mythtv wiki".

Marc
Page 1 of 1 All times are UTC - 6 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/