28 Sep
2007
28 Sep
'07
4:52 a.m.
Hallo!
our experience with ardour has been that DC bias is
measurably more
effective at reducing CPU load than DAZ, FTZ or both combined. DAZ and
FTZ do both help significantly, however.
One more question: is it not necessary to deactivate DAZ, FTZ again
after the application (or operation) ?
Or is this done automatically ?
(because I cannot see it e.g. in your ardour code)
Because e.g. in this document:
http://developer.apple.com/documentation/Performance/Conceptual/Accelerate_…
they set it back afterwards.
Thanks,
LG
Georg
28 Sep
28 Sep
7:22 a.m.
New subject: denormal handling
On 28 Sep 2007, at 07:51, Georg Holzmann wrote:
Hallo!
The kernel is responsible for setting it back when it switches away
from your process, otherwise it would be a disaster for other processes.
our experience with ardour has been that DC bias
is measurably more
effective at reducing CPU load than DAZ, FTZ or both combined. DAZ
and
FTZ do both help significantly, however.
One more question: is it not necessary to deactivate DAZ, FTZ again
after the application (or operation) ?
Or is this done automatically ?
(because I cannot see it e.g. in your ardour code) Because e.g. in this document:
http://developer.apple.com/
documentation/Performance/Conceptual/Accelerate_sse_migration/
migration_sse_translation/chapter_4_section_2.html#//apple_ref/doc/
uid/TP40002729-CH248-279676
they set it back afterwards.
Probably because they wanted to demonstrate how to turn it back on
for later bits of code within your process that might want denormals.
- Steve
6262
days inactive
6262
days old
linux-audio-dev@lists.linuxaudio.org
2 comments
2 participants
participants (2)
-
Georg Holzmann -
Steve Harris