[mythtv-users] Memory usage -- Is 256 MB enough?

[Johnson, Thor]

I'm using 0.16.  It seems ok as long as I don't watch recordings while
I'm recording+commercialflagging+transcoding.  And it's only done it a
few times (just annoying those few...).

I tried running without swap, and I'm confused by the results:
  Menus are snappy, but kswapd.0 is taking 86-90% of the CPU, so
    watching TV (live or memorex) is unusable.  Why would kswapd
    do anything if I don't have swap mounted?

  As soon as I mounted swap, 25MB immediately flew into it, and the CPU
    dropped to 0.5% (top). Swap kept on growing while I was transcoding
to 
    remove commercials.  I haven't looked again to see if it goes back 
    down after xcode is complete (it should)...

So... err... now what?
-Thor Johnson

-----Original Message-----
From: mythtv-users-bounces at mythtv.org
[mailto:mythtv-users-bounces at mythtv.org] On Behalf Of David Wood
Sent: Thursday, January 27, 2005 10:57 AM
To: Discussion about mythtv
Subject: Re: [mythtv-users] Memory usage -- Is 256 MB enough?

I run with 256 and have not had this problem (and I do transcode).

What version of myth are you using? 0.16? CVS?

On Thu, 27 Jan 2005, Johnson, Thor wrote:

> Hrm... I'm trying to run frontend+backend on a AthlonXP2500+ with 256
MB
> of ram (Gentoo 2.6.10), using a BT878 tuner (I want to add the pcHDTV,
> but since my TV is low-def it's not a priority.  Though I've noticed
> that NFL coverage has changed so you can't really see what's going on
> without Widescreen, so I wanted to do letterboxing with the pcHDtv --
> but that is a different discussion ;).
>
> Things on the box:
>   myth (frontend, backend)
>   mythweb (apache2, php5)
>   ssh, metalog, vixiecron
>   ntp-client, smartmond, icewm
>   lvm2
>
> After booting, and it starts recording, it seems to hover around 2.5MB
> of swap used (fine by me).  After a few shows go by and the commercial
> flagging process fires off, sometimes (it hasn't always done this),
the
> swap used will go 150MB over the course of 30 minutes (most of the
> memory is "used" by mythtranscode), and the system will grind to a
> horrible halt (top reports 80-90% in I/O wait, and mythbackend starts
> complaining about running out of free audio buffers). killall
> mythtranscode will make the system usable again.
>
> Questions:
>  1.  What happened?  This has been working for a few months without
> problems.  The last thing I did was expand the XFS partition that I
> store my videos on.
>
>  2.  How much ram do others have in their box?  I thought 256 would be
> enough (I had problems with 128 in swap, but it would work most of the
> time).
>
>  3.  Any ideas on how to troubleshoot this?
>
> Thanks,
> Thor Johnson
>
>