Opened 13 years ago

Closed 13 years ago

Last modified 13 years ago

#9461 closed Bug Report (Invalid)

mythfrontend seems to busy-wait while running

Reported by: alex@… Owned by:
Priority: minor Milestone: unknown
Component: MythTV - General Version: Unspecified
Severity: medium Keywords:
Cc: Ticket locked: no

Description

I noticed that while mythfrontend was running, my load average was quite high compared to when it wasn't. I tried strace on it and it seems to constantly be doing this:

poll([{fd=3, events=POLLIN}, {fd=8, events=POLLIN}, {fd=7, events=POLLIN}, {fd=11, events=POLLIN}], 4, -1) = 1 ([{fd=3, revents=POLLIN}]) read(3, "A", 1) = 1 read(7, 0x14d02c4, 4096) = -1 EAGAIN (Resource temporarily unavailable) read(7, 0x14d02c4, 4096) = -1 EAGAIN (Resource temporarily unavailable)

And lsof reports fd 7 to be:

mythfront 18164 mythtv 7u unix 0xffff880085ea7380 0t0 213283 socket

Anyone know what might be going on here?

Attachments (4)

version.txt​ (777 bytes) - added by alex@… 13 years ago.
mythfrontend --version information
strace.txt​ (356 bytes) - added by alex@… 13 years ago.
strace repeated output
mythversion.txt​ (638 bytes) - added by Alex Macfarlane Smith <alex@…> 13 years ago.
mythfrontend --version information from 0.24 fixes
strace.txt.bz2​ (60.4 KB) - added by sphery 13 years ago.
Complete strace output, compressed

Download all attachments as: .zip

Change History (14)

Changed 13 years ago by alex@…

Attachment: version.txt​ added

mythfrontend --version information

Changed 13 years ago by alex@…

Attachment: strace.txt​ added

strace repeated output

comment:1 Changed 13 years ago by robertm

Resolution: → Invalid
Status: new → closed

Please start on the users list, this is not a valid bug report. It's likely you are using a theme with alphapulse or other effects. The Myth UI is not yet hardware accelerated in any substantial fashion.

comment:2 Changed 13 years ago by robertm

Resolution: Invalid
Status: closed → new

Saw the discussion in #mythtv after closing this, giving it to stuart since he didn't object to a bug being opened.

comment:3 Changed 13 years ago by robertm

Owner: set to stuartm
Status: new → assigned

comment:4 Changed 13 years ago by stuartm

Owner: stuartm deleted

comment:5 Changed 13 years ago by Alex Macfarlane Smith <alex@…>

As requested by Mike, I've attached the complete strace from updating to 0.24-fixes.

Changed 13 years ago by Alex Macfarlane Smith <alex@…>

Attachment: mythversion.txt​ added

mythfrontend --version information from 0.24 fixes

comment:6 Changed 13 years ago by Alex Macfarlane Smith <alex@…>

Actually it's too big to be attached, so I've uploaded it to ​http://www.archifishal.co.uk/~aardvark/mythtv/strace.txt

comment:7 Changed 13 years ago by Alex Macfarlane Smith <alex@…>

And I'm using MythCenter?-wide as my theme

comment:8 Changed 13 years ago by Kenni Lund [kenni a kelu dot dk]

Status: assigned → new

Changed 13 years ago by sphery

Attachment: strace.txt.bz2​ added

Complete strace output, compressed

comment:9 Changed 13 years ago by sphery

Resolution: → Invalid
Status: new → closed

Based on the strace output, it looks like your system is returning EAGAIN on attempting to access /tmp/.X11-unix/X0 . This looks to be normal X input polling.

comment:10 Changed 13 years ago by Alex Macfarlane Smith <alex@…>

Curious that mythfrontend seems to be doing it constantly though (I traced strace'ing kcalc randomly to see what it did and it's mostly idle, but wakes up occasionally to look at /tmp/.X11-unix/X0.) Don't suppose you worked out what the read(3, "A", 1) was? I tried to look through the trace and couldn't see when it was last opened that would cause that - I did wonder if that was the thing waking it up and the X0 access was just a side effect of that.

Anyway if I get some time I'll investigate further.

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