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Internet Message Format  |  2003-01-02  |  3KB
  1. Return-Path: <icon-group-sender>
  2. Received: (from root@localhost)
  3.     by baskerville.CS.Arizona.EDU (8.11.1/8.11.1) id gAMJZJ606887
  4.     for icon-group-addresses; Fri, 22 Nov 2002 12:35:19 -0700 (MST)
  5. Message-Id: <200211221935.gAMJZJ606887@baskerville.CS.Arizona.EDU>
  6. Subject: Re: Speed-up Icon's disk access?
  7. To: icon-group@cs.arizona.edu
  8. From: "Joel I Bolonick" <Joel.Bolonick@celeradiagnostics.com>
  9. Date: Fri, 22 Nov 2002 09:45:40 -0800
  10. X-MIMETrack: Serialize by Router on USFRMMTA01/FRM/PEC(Release 5.0.8 |June 18, 2001) at
  11.  11/22/2002 12:48:16 PM
  12. Errors-To: icon-group-errors@cs.arizona.edu
  13. Status: RO
  14.  
  15.  
  16. Interesting...I've also been curious as to why the random access
  17. performance of Icon on our Unix platform is so slow.
  18.  
  19. My assumption is that it is inherent in the access mode itself in that
  20. every random-access operation involves a separate disk "seek" operation
  21. rather than possibly reading from an existing  buffer, since one of my
  22. coworkers has had similar speed problems implementing random-access
  23. operations in C.  We finally dealt with the problem by create a RAM-disk on
  24. our Unix platform and reading the file into the RAM-disk before running the
  25. program.  I assume you can do something similar on Windows.
  26.  
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  30.                                                                                                               
  31.                     jleger@afslog                                                                             
  32.                     istics.com           To:     icon-group@CS.Arizona.EDU                                    
  33.                     (Jonathan            cc:                                                                  
  34.                     Leger)               Subject:     Speed-up Icon's disk access?                            
  35.                                                                                                               
  36.                     11/22/2002                                                                                
  37.                     06:03 AM                                                                                  
  38.                                                                                                               
  39.                                                                                                               
  40.  
  41.  
  42.  
  43.  
  44. Icon's disk access (at least on the Windows platform) is pretty darn
  45. fast, no doubt about it.  But just in case there are ways to improve
  46. it... are there?  I'm primarily interested in improving the random
  47. access speed.  If I buffer the input when reading straight through a
  48. file I can get a 20-25% increase in performance, but buffering when
  49. you're reading all over the file would probably slow down the
  50. performance.
  51.  
  52. Any ideas on improving Icon's random disk access short of using an
  53. external C library?
  54.  
  55. Thanks,
  56. Jonathan Leger
  57.  
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