comp-activ Database

The comp-activ databases is a collection of a computer systems activity measures . The data was collected from a Sun Sparcstation 20/712 with 128 Mbytes of memory running in a multi-user university department. Users would typically be doing a large variety of tasks ranging from accessing the internet, editing files or running very cpu-bound programs. The data was collected continuously on two separate occasions. On both occassions, system activity was gathered every 5 seconds. The final dataset is taken from both occasions with equal numbers of observations coming from each collection epoch in random order.

System measures used:

  1. lread - Reads (transfers per second ) between system memory and user memory
  2. lwrite - writes (transfers per second) between system memory and user memory
  3. scall - Number of system calls of all types per second
  4. sread - Number of system read calls per second .
  5. swrite - Number of system write calls per second .
  6. fork - Number of system fork calls per second.
  7. exec - Number of system exec calls per second.
  8. rchar - Number of characters transferred per second by system read calls
  9. wchar - Number of characters transfreed per second by system write calls
  10. pgout - Number of page out requests per second
  11. ppgout - Number of pages, paged out per second
  12. pgfree - Number of pages per second placed on the free list.
  13. pgscan - Number of pages checked if they can be freed per second
  14. atch - Number of page attaches (satisfying a page fault by reclaiming a page in memory) per second
  15. pgin - Number of page-in requests per second
  16. ppgin - Number of pages paged in per second
  17. pflt - Number of page faults caused by protection errors (copy-on-writes).
  18. vflt - Number of page faults caused by address translation .
  19. runqsz - Process run queue size
  20. freemem - Number of memory pages available to user processes
  21. freeswap - Number of disk blocks available for page swapping.
  22. usr - Portion of time (%) that cpus run in user mode
  23. sys - Portion of time (%) that cpus run in system mode
  24. wio - Portion of time (%) that cpus are idle waiting for block IO
  25. idle - Portion of time (%) that cpus are otherwise idle


Predict usr, portion of time, that cpus run in user mode from all attributes 1-21.
Predict usr using a restricted number (excluding the paging information 10-18) of attributes.

Last Updated 9 October 1996
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