IBM Z77-5054 tapeIOCStiming free download

File name Z77-5054_tapeIOCStiming.pdf

U~~ TECHNICAL rrIE 5-0054 . IJ IN'FORMATION February 16, 1965 : EXCHANGE 8 pages Revised 9/8/65 IO _~~ 11 - Sb5'1 IBM 1401 rrAPE IOCS TIJVIING CALCULATION FORMULAS To:m Scharf IBM Corp. DP Custonler Education Gladengvn 3 B Oslo, Norway FOR IBM INTERNAL USE ONLY This paper is in the author's ()riginal form. Th~~ objecti.ve in providing this copy is to keep you informed in your field of interest. Please do not distribute this paper to persons outside the Company. Distr ibuted by DPD Program Information Department IBM Corporation 112 East Post Road TIE 5-0054 White Plains, New York In:M: 1401 TAPE IOCS TIMING CALCULATION FORMULAS ABSTRACT The 1401 IOCS for a tape-based system has an un- Author: Torn Scharf expectedly high processing time which can be as high Date: January 12th 1965 as 110% of the pure tape time itself. Obviously this important factor must be taken into account for any timing calculation but these figures are not, to the au- thors knowledge, previously published. The formulas are worked out on the basis of a typical fixed blocked DTF using a combination read/write DIOCS subroutine. Direct The exact time for every single instruction which is In qui r i e s t 0 : TOM SCHARF normally run through was calculated. The timings thus IBM DP CUSTOMER EDUCATION calculated theoretically correlate very well with actual GLADENGVN 3B timing comparisons performed with and without IOCS. OSLO NORWAY :BLOC.K ' II/D} 7~ IceS - V{C'~. FACTOR ~oo E ART SHOWINEt ~E.lATION5H'P B