LinuxMCE Forums
May 23, 2013, 01:31:21 pm GMT-1 *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with username, password and session length
News: Rule #1 - Be Patient - Rule #2 - Don't ask when, if you don't contribute - Rule #3 - You have coding skills - LinuxMCE's small brother is available: http://www.agocontrol.com
 
   Home   Help Search Chat Login Register  
Pages: [1]
  Print  
Author Topic: CPU usage of generic serial device  (Read 268 times)
b4rney
Guru
****
Posts: 454


View Profile
« on: October 29, 2011, 01:11:18 pm »

Hi Guys,

I've been trying to diagnose why my video media keeps freezing for a couple of seconds then quickly catching up again on my MD. This happens at regular 1-2 minute intervals.

I noticed on all my MDs that when I run 'top' I see 'Generic_Serial_' at the top of the list using 14% cpu. If I have more than one attached AV device then there are two of these (so 28% cpu). My devices are an LG TV and a Denon amp.

Question is ... Is This Normal? That is a lot of CPU for something that is not in use 99.99% of the time. It is more CPU than xine player when watching videos.

I'm running 0810 updated within the last two weeks. VDPAU enabled on my acer revo md (the one that skips).

Barney
Logged
posde
Administrator
LinuxMCE God
*****
Posts: 2621


Wastes Life On LinuxMCE Since 2007


View Profile WWW
« Reply #1 on: October 29, 2011, 03:35:00 pm »

That's normal, and does not interfere with watching video on my system. I have a Denon amp and a JVC projector connected to a ION based system, and do not see any glitches. I do see the high CPU load which is typical for those RS-232 connections.
Logged

tschak909
LinuxMCE God
****
Posts: 5101

DOES work for LinuxMCE.


View Profile
« Reply #2 on: October 29, 2011, 07:41:02 pm »

Don't worry about it. Why?

It has to do with the sleep() during the process idle thread in GSD. This is normal, and only marks the GSD process as mostly waiting, which of course, results in a higher load average. It does not affect the CPU usage, as no CPU usage is used during a sleep() except to count how long to sleep. This is a simple set of x86 instructions that take at most 8 CPU cycles each iteration, and seeing that a GHz CPU executes cycles in the billions per second, it's a bit like trying to track down a gnat flying through an airport. Wasteful, and ultimately doesn't mean anything.

-Thom
Logged
b4rney
Guru
****
Posts: 454


View Profile
« Reply #3 on: October 29, 2011, 10:50:57 pm »

Thanks guys.

I will leave the gnat in search of bigger prey!

Maybe just rebuilding the md in question will squash the glitches.

Cheers
Barney
Logged
Pages: [1]
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!