ref: 75c92428225428c8fde2d015f010e608a0b12f1d
dir: purgatorio/man/4/grid-cpu
.TH GRID-CPU 4
.SH NAME
grid: cpu \- cpu server resource
.SH SYNOPSIS
.B grid/srv/cpu
.br
.B grid/runcpu
.SH DESCRIPTION
.I Cpu
is a file server that provides a processing resource. This resource imports a namespace from one or more external sources and executes selected commands within it.
.I Cpu
creates its own namespace containing three files
.BR ctl ,
.B cmd
and
.B ns
which are used to configure the processing task prior to execution, this namespace is exported and served on
.I stdin.
In order to configure a processing task, a client must first mount the
.I cpu
namespace. Once this is done, reading the
.B cmd
and
.B ns
files will display the current configuration of commands to be executed or directories to be imported respectively. The
.B ctl
file is used to modify the current configuration and accepts the following input:
.IP
.B add cmd
.I command
.IP
.B add ns
.I path address
.IP
.B del [cmd|ns]
.I index
.PP
Where
.I command
is the name (including full path and parameters) of a command to be executed.
.I Path
is the name of a directory to import from the exported namespace available at
.I address
and
.I index
is the index (as shown when reading the
.B cmd
and
.B ns
files) of the command or directory to be removed from the configuration.
.PP
For example, to import
.B /dis
and
.B /dev
from a resource exporting a 9P (see
.IR intro(5))
namespace at address
.B tcp!200.1.5.53!7003
and then run
.B ls -l
and
.BR du ,
the following commands would be used:
.IP
.B "echo 'add cmd /dis/ls -l' > ctl"
.br
.B "echo 'add cmd /dis/du' > ctl"
.br
.B "echo 'add ns /dis tcp!200.1.5.53!7003' > ctl"
.br
.B "echo 'add ns /dev tcp!200.1.5.53!7003' > ctl"
.PP
Reading the
.B cmd
and
.B ns
files will give the following output:
.IP
.B cmd
.br
.B 1: /dis/ls -l
.br
.B 2: /dis/du
.IP
.B ns
.br
.B 1: /dis (200.1.5.53!7003)
.br
.B 2: /dev (200.1.5.53!7003)
.PP
Once the client disconnects from (unmounts) the cpu, the selected namespaces will be imported and the commands executed. Note: A
.I cpu
does not have
.I any
namespace of its own. All required namespaces
.I must
be imported, for a simple command such as
.BR ls ,
the minimum recommended namespace to import would be:
.B /chan /dev /dis /module
.PP
.IR Register (1)
may be used in conjunction with
.I cpu
to register it with a
.IR registry (4)
and to export and serve its namespace across
.IR dial(2)
network connections. Incoming connections may also be displayed visually using
.IR grid-monitor (1).
For example:
.PP
.BI "grid/register [" " options ..." " ] { grid/srv/cpu } | grid/srv/monitor 2 'CPU resource'
.PP
This set of commands is encapsulated within the shell script
.I runcpu
which will automatically register
.I cpu
with a
.IR registry(4)
if possible and start up the graphical display to show connections to the resource. There is no need for the user to execute
.I cpu
outside of
.I runcpu
unless the namespace it provides is required to be accessible in a different way to that provided by
.IR grid-register (1).
.SH SOURCE
.B /appl/grid/srv/cpu.b
.SH BUGS
At the moment,
.I Cpu
will only import namespaces across an unauthenticated connection as provided by
.IR ns (1).
.SH "SEE ALSO"
.IR grid-monitor (1),
.IR grid-ns (1),
.IR grid-query (1),
.IR grid-register (1)