Mailing List Archive: MythTV: Commits

Ticket #10541: SIGSEGV when EIT updating DB and channel change

Index | Next | Previous | View Threaded

noreply at mythtv

Apr 3, 2012, 10:32 AM

Post #1 of 13 (152 views)
Permalink

Ticket #10541: SIGSEGV when EIT updating DB and channel change

#10541: SIGSEGV when EIT updating DB and channel change
--------------------------------------+-------------------------
Reporter: angela.schmid@… | Owner: danielk
Type: Bug Report - General | Status: new
Priority: major | Milestone: 0.25
Component: MythTV - DVB | Version: Master Head
Severity: high | Keywords:
Ticket locked: 0 |
--------------------------------------+-------------------------
I have a reproducible problem and tried several 0.25-pre versions since
the beginning of march. On a channel change for a recording and a running
(or maybe just ending) EIT update to the DB I get a SIGSEGV, almost every
second day. Sometimes empty files are created prior the crash of
mythbackend.

Reply from Michael:
Got a chance to look over the back trace and it's definitely a bug in our
code--the EIT scanner is not being shut down properly and is trying to
change channel on a null TVRec. It may be related to
http://code.mythtv.org/trac/ticket/10016 , but at this point it makes
sense to just create a new ticket for it. Please attach your log file and
back trace to the ticket (or let me know if it refuses to let you due to
the spam filter--which might not be working properly after the move to the
new server--and I can upload them for you).

--
Ticket URL: <http://code.mythtv.org/trac/ticket/10541>
MythTV <http://code.mythtv.org/trac>
MythTV Media Center
_______________________________________________
mythtv-commits mailing list
mythtv-commits [at] mythtv
http://www.mythtv.org/mailman/listinfo/mythtv-commits

noreply at mythtv

Apr 3, 2012, 10:57 AM

Post #2 of 13 (144 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

noreply at mythtv

Apr 7, 2012, 9:23 AM

Post #3 of 13 (131 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

noreply at mythtv

Apr 8, 2012, 4:43 AM

Post #4 of 13 (131 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

#10541: SIGSEGV when EIT updating DB and channel change
--------------------------------+-----------------------------
Reporter: angela.schmid@… | Owner: danielk
Type: Bug Report - Crash | Status: new
Priority: major | Milestone: 0.25
Component: MythTV - DVB | Version: Master Head
Severity: high | Resolution:
Keywords: | Ticket locked: 0
--------------------------------+-----------------------------

Comment (by angela.schmid@…):

Hi Daniel,
I pulled and activated the patch. A 0 byte file was created at 05:10,
however the logs show only ASK_RECORDING 30 seconds before. I think not
everything get logged, EIT debug messages overwrite the channel changing
messages. The frontend loosed connection and I had to ctrl-c the gdb'ed
backend. Attached is the dbg.txt and mythbackend.log.

Angela

2012-04-08 05:16:17.836800 E ThemeInfo: The theme
(myth://Temp [at] 127/remotethemes/trunk/Arclight) is missing a
themeinfo.xml file.
2012-04-08 05:16:27.829562 E MythSocket(28e6dc0:32): readStringList:
Error, timed out after 30000 ms.
2012-04-08 05:16:27.829600 C Protocol version check failure.
The response to MYTH_PROTO_VERSION was empty.
This happens when the backend is too busy to
respond,
or has deadlocked in due to bugs or hardware
failure.
2012-04-08 05:16:27.829607 E RemoteFile::openSocket(control socket):
Failed validation to server 127.0.0.1:6543
2012-04-08 06:16:17.834741 E ThemeInfo: The theme
(myth://Temp [at] 127/remotethemes/trunk/Arclight) is missing a
themeinfo.xml file.
2012-04-08 06:16:27.829810 E MythSocket(28a1710:32): readStringList:
Error, timed out after 30000 ms.
2012-04-08 06:16:27.829848 C Protocol version check failure.
The response to MYTH_PROTO_VERSION was empty.
This happens when the backend is too busy to
respond,
or has deadlocked in due to bugs or hardware
failure.
2012-04-08 06:16:27.829855 E RemoteFile::openSocket(control socket):
Failed validation to server 127.0.0.1:6543
2012-04-08 07:16:17.836478 E ThemeInfo: The theme
(myth://Temp [at] 127/remotethemes/trunk/Arclight) is missing a
themeinfo.xml file.
2012-04-08 07:16:27.832667 E MythSocket(2317e20:32): readStringList:
Error, timed out after 30000 ms.
2012-04-08 07:16:27.832703 C Protocol version check failure.
The response to MYTH_PROTO_VERSION was empty.
This happens when the backend is too busy to
respond,
or has deadlocked in due to bugs or hardware
failure.
2012-04-08 07:16:27.832710 E RemoteFile::openSocket(control socket):
Failed validation to server 127.0.0.1:6543

--
Ticket URL: <http://code.mythtv.org/trac/ticket/10541#comment:3>
MythTV <http://code.mythtv.org/trac>
MythTV Media Center
_______________________________________________
mythtv-commits mailing list
mythtv-commits [at] mythtv
http://www.mythtv.org/mailman/listinfo/mythtv-commits

noreply at mythtv

Apr 8, 2012, 8:14 AM

Post #5 of 13 (127 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

noreply at mythtv

Apr 8, 2012, 1:31 PM

Post #6 of 13 (126 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

noreply at mythtv

Apr 12, 2012, 12:56 PM

Post #7 of 13 (121 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

noreply at mythtv

Apr 15, 2012, 9:50 AM

Post #8 of 13 (115 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

#10541: SIGSEGV when EIT updating DB and channel change
--------------------------------+--------------------------------
Reporter: angela.schmid@… | Owner: danielk
Type: Bug Report - Crash | Status: infoneeded_new
Priority: minor | Milestone: 0.26
Component: MythTV - DVB | Version: Master Head
Severity: low | Resolution:
Keywords: | Ticket locked: 0
--------------------------------+--------------------------------

Comment (by angela.schmid@…):

Hello

No crashes anymore. However I see mythbackend hanging, which I have seen
in the past also without this patch.
I restarted mythbackend. EIT passive scanning started (17:39:26). A
recording was asked (17:39:39). EIT writing from 17:40:01 till 17:43:16.
During this time mythweb was not responding. Socket errors were
protocolied at 17:43:31. Recording was canceled 17:43:32. Mythweb did not
respond. A yet started mythfrontend had a log time to scan the recordings
in watch recordings. Had to restart mythbackend.

During "EITCache: Wrote 14 modified entries of 252 for channel 1002 to
database" messages, I think mythbackend comes unresponsive, this behaviour
has been seen before, also without this patch.
This time the recording has been canceled. In my previous comment, the
recording started 1.5 minutes later.

Run with " /usr/bin/mythbackend --syslog local7 --user mythtv -v
eit,general --loglevel debug". Attached mythbackend.zip and gdb1.txt (gdb
-p <pid>).
Why does mythbackend hang.

Angela

p.s. Why does MythTV not reuse prepared statements ? For each
insert/update/delete as far as I have seen, the SQL command is prepared on
each call. Why not preparing it once and reuse it. Sure needs some re-
preparing when the connection has to be re-astablished. Writing 2000 EIT
records needs 3 Minutes, which is in my eyes very long. This is on a Sandy
Bridge 2600K.

--
Ticket URL: <http://code.mythtv.org/trac/ticket/10541#comment:7>
MythTV <http://code.mythtv.org/trac>
MythTV Media Center
_______________________________________________
mythtv-commits mailing list
mythtv-commits [at] mythtv
http://www.mythtv.org/mailman/listinfo/mythtv-commits

noreply at mythtv

Apr 18, 2012, 7:31 AM

Post #9 of 13 (116 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

noreply at mythtv

May 4, 2012, 11:09 AM

Post #10 of 13 (100 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

noreply at mythtv

May 4, 2012, 11:12 AM

Post #11 of 13 (100 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

noreply at mythtv

May 27, 2012, 7:58 AM

Post #12 of 13 (90 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

noreply at mythtv

May 29, 2012, 5:37 AM

Post #13 of 13 (87 views)
Permalink

Re: Ticket #10541: SIGSEGV when EIT updating DB and channel change [In reply to]

Index | Next | Previous | View Threaded

Interested in having your list archived? Contact Gossamer Threads