This bulletin contains instruction timing in- formation for all models of the 8ystem/360. For a full description of each instruction, refer to IBM 8ystem/360 Principles of Operation, Form A22-6821. MAJOR REVISION (May 1964) This publication, Form A22-6825-1, obsoletes Form A22-6825-0, N22-0133, and N22-0135.
Copies of this and other IBM publications can be obtained through IBM Branch Offices. Address comments concerning the contents of this publication to: IBM Corporation, Customer Manuals, Dept. 898, PO Box 390, Poughkeepsie, N.Y. 12602 SYSTEM/360 INSTRUCTION TIMING INFORMATION
The instruction time tables presented in this bulletin 2. In all storage operations, positive and negative provide average instruction times, in microseconds, operands are equally probable. f~r all models of the IBM System/360. All times for 3. Each bit location has equal probability for the instructions that reference storage include the time binary values 0 or 1, and each bit location is required to perform single indexing by one general independent of other bit locations. Decimal data register as referenced in the instruction (i. e., B 1= 0) . may contain digit values 0 to 9 in eaoh digit For those instructions in which indexing may be per- position with equal probability. formed two times (i. e. , all RX format instructions), 4. Variable field length instructions may start on the time required for the second indexing must be even or odd halfwords with equal probability. added to the basic time given in the table, as follows: 5. Interruptions or masked-off program exceptions are not reflected in these timings. MODEL ADDITIONAL TIME (in microseconds) TIMING ASSUMPTIONS 30 6.0 40 1.25 SO 0.5 The following assumptions were used in the devel- 60 0.125 opment of these instruction time tables. 62 0.125 70 0.0 1. For decimal-add and decimal-subtract instruc- tions, the first operand (i. e. , the destination The instructions that may be indexed a second field) is assumed to be greater than, or equal time are highlighted by an asterisk in the table. to, the length of the second operand (i. e. , the source field). TIMING CONDITIONS 2. For decimal-add and decimal-subtract instruc- tions, recomplementation time is not included The following conditions were used in the develop- in the times given. ment of these instruction time tables. 3. In the EDIT AND MARK (EDMK) instruction, 1. All instruction timings pertain only to storage an address is stored once. That is, this instruc- references to main storage as follows: tion is used with a single field, or a line with only one numeric field rather than a complete print line. MODEL SPEED (in microseconds) WIDTH (in bytes) 4. In the TRANSLATE AND TEST (TRT) instruc- tion, it is assumed that a non-zero byte from 30 2.0 1 40 2.5 ' 2 the Translate and Test table is found. SO 2.0 4 5. The instruction times for the floating-point in- 60 2.0* 8 structions depend -upon the number of hexidecimal 62 1.0 8 digits that are pre shifted and postshifted, as well 70 1.0* 8 as the number of times recomplementation of a * Interleaved. Provides reduced access time for consecutively result occurs. The times given in the instruction addressed references by overlapping storage cycles of odd time tables for floating-point instructions are and even addresses. a weighted average of these variables.
3 SYSTEM / 360
MODEL 30 40 50 60 62 70 INSTRUCTION FORMAT MNEMONIC Time Time Time Time Time Time Blo Blo Blo Blo BIO s/o
