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faq:start [2012/05/25 22:09] – [Q: How to remove noise ? How to restore old recordings (from vinyl/tape) ?] emrumfaq:start [2015/11/16 11:02] – [Q: What about timers and timing ?] 202.77.55.169
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 ====== Linux Audio User FAQ (Frequently Asked Questions) ====== ====== Linux Audio User FAQ (Frequently Asked Questions) ======
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 ===== General ===== ===== General =====
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 ==== Q: What about timers and timing ? ==== ==== Q: What about timers and timing ? ====
-Modern PCs provide good hardware timing sources. +For moderate to new hardware, TSC is the best hardware timing sources.  Old hardware may have timing issues with multi-core CPU where HPET (high-precision-event-timer) is preferable.
-One of it is the RTC (real-time-clock). Another one is the HPET (high-precision-event-timer), which is preferable due to higher accuracy.+
 Then there is a software layer (in the kernel) to make available the hw-timers to the applications, through different interfaces. Then there is a software layer (in the kernel) to make available the hw-timers to the applications, through different interfaces.
 One example is the usual system-timer. One example is the usual system-timer.
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 (see: priority settings, rtirq). (see: priority settings, rtirq).
  
-**How to know, if a HPET (hardware) is available?**+**How to know, if a TSC / HPET (hardware) is available?** 
 +  dmesg | grep -i tsc
   dmesg | grep -i hpet   dmesg | grep -i hpet
  
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   cat /proc/asound/timers   cat /proc/asound/timers
  
-**Related Kernel Options **+**How to config kernel for HPET?**
 <code> <code>
 # cat .config | grep -i hpet # cat .config | grep -i hpet
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 Related Articles: Related Articles:
 [[http://kerneltrap.org/node/6750| Article at kerneltrap.org]] [[http://kerneltrap.org/node/6750| Article at kerneltrap.org]]
 +[[http://btorpey.github.io/blog/2014/02/18/clock-sources-in-linux/]]
  
  
faq/start.txt · Last modified: 2017/08/26 17:21 by jeb_ponderworthy.com