1988 Ed.]
Import and Export (Strategic Commodities) Regulations
[CAP. 60
G 115
[Subsidiary]
'execution time'
(a) The time certified or openly published by the manufacturer for the execution of the fastest appropriate instruction, under the following conditions:
(1) No indexing or indirect operations are included;
(2) The instruction is in the "most immediate storage”;
(3) One operand is in the accumulator or in a location of the "most immediate storage”, which is acting as the accumulator;
(4) The second operand is in the most immediate storage”; and (5) The result is left in the accumulator or the same location in the "most immediate storage", which is acting as the accumulator;
(b) If only the maximum and minimum execution times of the instructions are published, the sum of;
(1) The maximum execution time of an instruction (tmax); and
(2) Twice the minimum execution time of this instruction (tmin); Divided by three
(c)
tmax + 2tmin
Thus: t = ---------------
3
(t stands for any of the values taxı tafa tmx: or tmf);
(d) For central processing units which simultaneously fetch more than one instruction from one storage location:
The average of the 'execution times' when executing instructions fetched from all possible locations within the stored word.
(e) If the longest fixed point operand length is smaller than 16-bit, then use the time required for the fastest available subroutine to simulate a 16-bit fixed point operation.
N.B.
1. If the addressing capability of an instruction is expanded by using a base register, then the 'execution time' shall include the time for adding the content of the base register to the address part of the instruction.
2. When calculating 'processing data rate' for computers with cache sizes smaller than 64K Bytes, the 'execution time' of the appropriate instructions will be calculated as follows:
(cache hit rate) x ("execution time' when both instruction and operand are in cache storage)+(1-cache hit rate) x (execution time" when neither instruction nor operand are in cache storage),
The cache hit rate being:
1.00 for cache size of 64K Byte
0.95 for cache size of 32K Byte
0.90 for cache size of 16K Byte
0.85 for cache size of 8K Byte
0.75 for cache size of 4K Byte
"total transfer rate”-
(a) of the input/output control unit-drum, disk or cartridge-type streamer tape drive combinations (Rtot):
The sum of the individual 'transfer rates' of all input/output control unit-drum, disk or cartridge-type streamer tape drive combinations (rtd) provided with the system which can be sustained simultaneously assuming the configuration of equipment which would maximize this sum of rates.
Thus: Rtot = SUM Rtd:
(1) Of an input/output control unit-drum or disk drive combination (R1d), the smaller of either:
N.B. For the 'transfer rate' of an input/output control unit-cartridge-type streamer tape drive combination, see (b) below.
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