[mythtv-users] S-L-O-W DB ops

[Steve]

On Nov 12, 2011, at 11:30 AM, Jerry <mythtv at hambone.e4ward.com> wrote:

> On Fri, Nov 11, 2011 at 11:37 PM, Mark Lord <mythtv at rtr.ca> wrote:
> On 11-11-11 07:55 PM, MythTV wrote:
> > On 11/11/2011 05:52 PM, networks1 at cox.net wrote:
> >> ============================= Thanks for the input. So I had a look at
> >> the entry in fstab and right now it's "defaults." Did you change to
> >> defaults,nobarrier or just replace it with nobarrier? I also found
> >> https://wiki.archlinux.org/index.php/Ext4 which says "Users can
> >> improve performance with the nobarrier option when mounting the disk,
> >> but this can be dangerous [2] and may result in data loss or
> >> corruption after power failures. To turn barriers off, add the option
> >> barrier=0 to the desired filesystem" So I presume that's the right
> >> thing to do, but again append it after defaults, or replace? Steve
> >
> > Just append it:
> >
> > defaults,nobarrier
> 
> Or even simplier, just put:   nobarrier
> in place of "defaults".
> 
> I am experiencing the same issues.  I am hesitant to use the nobarrier option.  I have a UPS but it doesn't seem like the safest thing.
> 
> Let me also say that I am in a little over my head here.  I did some searching on in the mythtv-users archive and came up with this message from last month:
> 
> http://www.mailinglistarchive.com/html/mythtv-users@mythtv.org/2011-10/msg00529.html
> 
> I followed the suggestions; that is, appending journal_async_commit,noatime,nodiratime to my mount options in /etc/fstab/  Previously, mythfilldatabase took 20 minutes to run (data was already present).  Now, it takes 10 minutes.  It's still not as fast as using nobarrier but it's a vast improvement.
> 
> I'm still open to suggestion.  Your mileage may vary.  :)
> ______________________________

I would add to this that even after adding barrier=0 it speeded up MySQL but the frontend and setup interfaces are extremely sluggish. I don't know if this is because of the disk or Gnome 3, which others have warned is a resource hog. If its the latter it must be a pretty big hog because I'm running on a dual core 3ghz processor. 
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