Effects of clock resolution on the scheduling of interactive and real-time processes

Yoav Etsion*, Dan Tsafrir, Dror G. Feitelson

*Corresponding author for this work

Research output: Contribution to journalConference articlepeer-review

20 Scopus citations


It is commonly agreed that scheduling mechanisms in general purpose operating systems do not provide adequate support for modern interactive applications, notably multimedia applications. The common solution to this problem is to devise specialized scheduling mechanisms that take the specific needs of such applications into account. A much simpler alternative is to better tune existing systems. In particular, we show that conventional scheduling algorithms typically only have little and possibly misleading information regarding the CPU usage of processes, because increasing CPU rates have caused the common 100 Hz clock interrupt rate to be coarser than most application time quanta. We therefore conduct an experimental analysis of what happens if this rate is significantly increased. Results indicate that much higher clock interrupt rates are possible with acceptable overheads, and lead to much better information. In addition we show that increasing the clock rate can provide a measure of support for soft real-time requirements, even when using a general-purpose operating system. For example, we achieve a sub-millisecond latency under heavily loaded conditions.

Original languageAmerican English
Pages (from-to)172-183
Number of pages12
JournalPerformance Evaluation Review
Issue number1
StatePublished - Jun 2003
EventACM SIGMETRICS 2003 - International Conference on Measurement and Modeling of Computer Systems - San Diego, CA, United States
Duration: 10 Jun 200314 Jun 2003


  • Clock interrupt rate
  • Interactive process
  • Linux
  • Overhead
  • Scheduling
  • Soft real-time
  • Tuning


Dive into the research topics of 'Effects of clock resolution on the scheduling of interactive and real-time processes'. Together they form a unique fingerprint.

Cite this