New subject: External USB 2 HD for real-time recording

9 Mar 2013

On Sat, March 9, 2013 9:49 am, Peder Hedlund wrote:
...
  Quoting Len Ovens &lt;len(a)ovenwerks.net&gt;et>:

 The previous reply was due to a trigger happy Send finger, sorry about
 that... 
been there...

...
    An obvious workaround would be having a cron job doing
a 'touch
 TempFile' or something similar on the disk once every 5 minutes or so. 
 Would that actually touch the disk or just the copy of the temp file in
 the ram buffers? 
 Initially it would only hit the cache but I think it's be written to
 disk within the remaining five minutes. 
I would guess it would depend on how busy the system was. I don't think it
would be high priority on a system running real time audio tasks. I don't
know enough about background disk writing to really say though.

...
  You could issue a 'sync' but I'm not sure
a forced sync during, say, a
 recording would be the proper thing to do, since it syncs all cached
 data on all disks. 
Ya that was my thought too.
...

 Another option would be to do a 'dd if=/dev/zero of=TestFile bs=1k
 count=1 conv=fdatasync' to make sure the data gets written to disk
 immediately (http://romanrm.ru/en/dd-benchmark). 
Run in a script with sleep, not from cron which might be turned off for
recording :)  apt-get update running in the BG is enough to give me xruns
sometimes (I am not sure it is apt-get itself, but there is system disk
and network activity too)

-- 
Len Ovens
www.OvenWerks.net

Re: [LAU] External USB 2 HD for real-time recording