30 Nov
2017
30 Nov
'17
6:15 p.m.
Peter <list-uRjC9i54a0HBwHGg3TQQPgC/G2K4zDHf(a)public.gmane.org> writes:
Dear Jeanette,
Am 30.11.2017 um 16:54 schrieb Jeanette C.:
Well, Jeannette stated that she was replaying 4 stereo tracks at the
same time she was recording five. With a buffer size of 256 samples
(using ALSA, this implies a default of only 2 buffers). This kind of
double-duty regarding playback/record is more problematic for rotating
disks (and this is a 5400 rpm disk) than it would be for solid-state
drives. Playing with the disk parameters (in particular to avoid the
less time-critical bulk writes delaying the playback reads) might help.
Frankly, I'd consider recording to SDHC card (they are quite cheaper
than a SSD drive which would be the better option).
But of course, increasing buffer size might be all that is needed. The
only reason for smaller buffer size is real-time monitoring and/or
real-time effects. Monitoring might be doable in analog (personally, I
am using a mixer with recording interface in order to be able to do
that). Multitracking as such does not need small buffers: the delays
can be properly compensated by latency management.
--
David Kastrup
Hey hey,
after further analysis, I find that my hard drive seems to be the
problem. I can't write fast enough. Playback of multiple tracks is
no issue (ca. 10 stereo tracks, 32bit, 48kHz), but 5 stereo tracks,
even from an external source, start to generate hiccoughs.
Can it be that the drive is really that bad, or is there a parameter
to tune, so this could be improved?
this looks indeed pretty slow, is it an external usb-2 drive?
You may perform a simple check:
sudo hdparm -tT /dev/sda
Replace sda with your device.
If your are just recording, can you increase the buffer length in jack?
I was recently recording 32 mono channels and got initially lots of
xruns in ardour,
which disappeared after increasing the buffer size in jack.