Developer Reference

  • 0.9
  • 09/09/2020
  • Public Content
Contents

blacs_pinfo

Returns the number of processes available for use.

Syntax

call blacs_pinfo
(
mypnum
,
nprocs
)
Output Parameters
mypnum
INTEGER
. An integer between 0 and (
nprocs
- 1) that uniquely identifies each process.
nprocs
INTEGER
.The number of processes available for BLACS use.
Description
This routine is used when some initial system information is required before the BLACS are set up. On all platforms except PVM,
nprocs
is the actual number of processes available for use, that is,
nprows
*
npcols
<=
nprocs
. In PVM, the virtual machine may not have been set up before this call, and therefore no parallel machine exists. In this case,
nprocs
is returned as less than one. If a process has been spawned via the keyboard, it receives
mypnum
of 0, and all other processes get
mypnum
of -1. As a result, the user can distinguish between processes. Only after the virtual machine has been set up via a call to
BLACS_SETUP
, this routine returns the correct values for
mypnum
and
nprocs
.

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804