摘要:
A system, method and computer program product for calibrating a Time Of Day (TOD)-clock in a computing system node provided in a multi-node network. The network comprises an infrastructure of computing devices each having a physical clock providing a time base for executing operations that is stepped to a common oscillator. The system implements steps for obtaining samples of timing values of a computing device in the network, the values including a physical clock value maintained at that device and a TOD-offset value; computing an oscillator skew value from the samples; setting a fine steering rate value as equal to the opposite of the computed oscillator skew value; and, utilizing the fine steering rate value to adjust the physical clock value and correct for potential oscillator skew errors occurring in the oscillator crystal at the computing device.
摘要:
A protocol for communicating with the timing facility used in a data processing network to provide synchronization is provided via the execution of a machine instruction that accepts a plurality of commands. The interaction is provided through the use of message request blocks and their associated message response blocks. In this way timing parameters may be determined, modified and communicated. This makes it much easier for multiple servers or nodes in a data processing network to exist as a coordinated timing network and to thus more cooperatively operate on the larger yet identical data files.
摘要:
A system, method and computer program product for steering a time-of-day (TOD) clock for a computer system having a physical clock providing a time base for executing operations that is stepped to a common oscillator. The method includes receiving, at a processing unit, a request to change a clock steering rate used to control a TOD-clock offset value for the processing unit, the TOD-clock offset defined as a function of a start time (s), a base offset (b), and a steering rate (r). The unit schedules a next episode start time with which to update the TOD-clock offset value. After updating TOD-clock offset value (d) at the scheduled time, TOD-clock offset value is added to a physical-clock value (Tr) value to obtain a logical TOD-clock value (Tb), where the logical TOD-clock value is adjustable without adjusting a stepping rate of the oscillator.
摘要:
A decimal floating point finite number in a decimal floating point format is composed from the number in a different format. A decimal floating point format includes fields to hold information relating to the sign, exponent and significand of the decimal floating point finite number. Other decimal floating point data, including infinities and NaNs (not a number), are also composed. Decimal floating point data are also decomposed from the decimal floating point format to a different format.
摘要:
A decimal floating point finite number in a decimal floating point format is composed from the number in a different format. A decimal floating point format includes fields to hold information relating to the sign, exponent and significand of the decimal floating point finite number. Other decimal floating point data, including infinities and NaNs (not a number), are also composed. Decimal floating point data are also decomposed from the decimal floating point format to a different format. For composition and decomposition, one or more instructions may be employed, including a shift significand instruction.
摘要:
A method and system are disclosed for executing a machine instruction in a central processing unit. The method comprise the steps of obtaining a perform floating-point operation instruction; obtaining a test bit; and determining a value of the test bit. If the test bit has a first value, (a) a specified floating-point operation function is performed, and (b) a condition, code is set to a value determined by said specified function. If the test bit has a second value, (c) a check is made to determine if said specified function is valid and installed on the machine, (d) if said specified function is valid and installed on the machine, the condition code is set to one code value, and (c) if said specified function is either not valid or not installed on the machine, the condition code is set to a second code value.
摘要:
A system, method and computer program product for performing a Perform Timing Facility (PTFF) instruction for steering a Time of Day (TOD) clock of the computer system for synchronizing the TOD clock with TOD clocks of other computer systems. The computer system comprises a memory; and, a processor in communications with the computer memory. The processor is capable of performing a PTFF instruction comprising: obtaining a function code specified in a first general register, the function code for identifying any one of a query function or a control function to be performed; obtaining, from a second general register, a memory address of a parameter block; responsive to the function code specifying a query function, storing timing information of the computer system in the parameter block according to the specified query function; responsive to the function code specifying a control function, using timing information obtained from the parameter block to perform the specified control function; and setting a condition code value indicating an outcome of the specified function.
摘要:
A time synchronization apparatus, method and system are provided. In one aspect, the apparatus comprises at least a time of day clock, a first port operable to receive at least first time information using a first time protocol, a second port operable to receive at least second time information using a second time protocol, a third port operable to receive at least a timing signal, and a time stamp register operable to at least capture current value of the time of day clock upon receipt of the timing signal from the third port or the first time information from the first port or combination thereof.
摘要:
Detection of whether a result of a floating point operation is safe. Characteristics of the result are examined to determine whether the result is safe or potentially unsafe, as defined by the user. An instruction is provided to facilitate detection of safe or potentially unsafe results.
摘要:
Two forms of TOD Clock instructions are provided, Store Clock and Store Clock Fast. Execution of the Store Clock Fast instruction may produce a time of day (TOD) result that is exactly the same as a previous TOD result, however execution of Store Clock Fast instructions while the clock is running always produce unique TOD results.