dxpresto.8

<B>Digital的Unix操作系统VAX 4.2源码</B>

.TH dxpresto 8
.SH Name
dxpresto \- graphically display Prestoserve state and statistics
.SH Syntax
\fB/usr/etc/dxpresto\fR [ \fIhostname\fR ] 
.PP
\fB/usr/etc/dxpresto\fR  \fIhostname\fR   \fIoptions\fR 
.SH Description
.NXR "dxpresto command"
.NXR "Prestoserve" "dxpresto command"
The 
.PN dxpresto
command is an 
.B X 
Window System application that
graphically displays a machine's Prestoserve state and statistics.  
The 
.PN dxpresto
command uses a Remote Procedure Call (RPC) protocol to communicate
with the machine being monitored.  You use the 
.PN dxpresto 
command to provide general information about Prestoserve and to help
manage Prestoserve.  Also, you can use the command to demonstrate the 
efficacy of the Prestoserve software. 
.PP
Use the
.IR hostname 
variable to specify the machine that you want to monitor; the machine must be 
running the Prestoserve software.  If
.IR hostname 
is not specified and options are not specified, then localhost, an alias for the 
local machine that is running the Prestoserve software, is used.  You must specify
.IR hostname
if you want to use options.
.NT
The machine that you want to monitor must be running the 
.PN prestoctl_svc
daemon.  Also, if you want to be able to enable or
disable Prestoserve on the machine, it must be running the 
.PN prestoctl_svc 
daemon with the 
.PN \-n
option.
.NE
.PP
Because 
.PN dxpresto
is an 
.B X
Window System application, your DISPLAY environmental variable must be
set to a machine that is an 
.B X
Server.  For more information, see 
.MS X 1X .
.PP
The 
.PN dxpresto
window shows the following information:
.IP \(bu 4
The 
.PN Host
field shows the name of the host that you are monitoring.  You can type
another host name in the field and hit the RETURN key to monitor that host.  
.IP \(bu 4
The 
.PN "Presto State"
buttons show the Prestoserve state, either Enabled (UP), Disabled (DOWN), or Error
(ERROR).  If the machine being monitored is running the 
.PN "prestoctl_svc"
daemon with the 
.PN \-n 
option, you can change the machine's Prestoserve state to either
Enabled (UP) or Disabled (DOWN) by clicking on the appropriate button.  
You cannot click on the Error button; contact
the server administrator or the server hardware Field Service representative 
if the Error button is enabled.
.IP \(bu 4
The 
.PN "Sample Interval"
slider shows the interval of time between Prestoserve 
queries, and it allows you to change that interval.  When you invoke the
.PN dxpresto
command, the default 
.PN "Sample Interval"
is 5; therefore Prestoserve information is gathered every five seconds.  
For example, if you want Prestoserve queried more often, move the slider to 
the left and click on MB1 until 2 appears;
Prestoserve is then queried every two seconds.
.IP \(bu 4
The 
.PN "Time since last Enable"
field shows the time since Prestoserve was last enabled. The time is displayed in
hours, minutes, and seconds.  The total number of seconds is also shown. 
.IP \(bu 4
The 
.PN "Size"
field displays the number of Kbytes of nonvolatile memory that the Prestoserve 
cache is utilizing.  Note that Prestoserve can utilize less than the
default maximum size of its Prestoserve cache if you changed the cache
size with the 
.PN "presto \-s"
command.
.IP \(bu 4
The 
.PN "Batteries"
graphics show the state of the Prestoserve backup battery system.
An intact battery icon with the word ok
indicates that the battery has sufficient power.  An intact battery
icon with the word
low indicates that the battery's power is low.  A broken battery icon
indicates that the battery is disabled.  Prestoserve goes into the ERROR state
when the backup battery power falls below a minimum amount.  Contact
the server administrator or the server hardware Field Service representative 
if a battery is low or disabled.
.IP \(bu 4
The 
.PN "Display Cache Utilization"
buttons allow you to display or to not display graphs that demonstrate how the 
Prestoserve cache is being utilized. 
.IP \(bu 4
The 
.PN "Display Cache Statistics"
buttons allow you to display or to not display the Prestoserve cache
statistics table.  
.IP \(bu 4
The
.PN Exit
button allows you to exit from 
.PN dxpresto .
.IP \(bu 4
The error bar displays error messages for both Prestoserve and the
.PN dxpresto 
command.  For example, if the 
.PN "prestoctl_svc"
daemon with the 
.PN \-n 
option is not running on the machine you are monitoring, then 
a message is displayed indicating that changes to Prestoserve operation
are not allowed.
.IP
Some error messages, such as those indicating RPC communication failure,
are displayed on the terminal from which you invoked the 
.PN dxpresto
command.  
.PP
If you display the
.PN "Display Cache Utilization" 
graphs, the following is shown:
.IP \(bu 4
The 
.PN "Presto buffers"
bar graph shows how the Prestoserve cache operations are distributed among
the four Prestoserve buffer states:  dirty, clean, inval, and active.
The vertical axis shows the maximum number of objects or disk blocks 
that the entire Prestoserve cache can contain.  The sum of the four bars is
the total number of buffers used in the Prestoserve cache.  
Note that the size of the Prestoserve cache can be changed by using the
.PN "presto \-s"
command.
.IP \(bu 4
The
.PN "Writes per second"
trend line graph shows a recent history of the average number of 
writes per second over the time intervals that are determined by the
.PN "Sample Interval"
slider.   
.IP
Each point in the horizontal axis represents a sample time interval
as determined by the 
.PN "Sample Interval" 
slider; the maximum number of samples that can be shown is 210.  
When you reach the maximum number of samples, the graph shifts to the 
left so you can see at least the last 105 samples, which is half the
maximum number of samples.
If you choose 5 in the 
.PN "Sample Interval"
slider, Prestoserve is queried every five seconds; therefore it takes
1050 (5 x 210) seconds to obtain the maximum of 210 samples.
.IP
The vertical axis shows the average number of writes performed per
second within the sample time interval as determined by the 
.PN "Sample Interval"
slider.
.IP
For example, if you choose 2 in the 
.PN "Sample Interval" 
slider, Prestoserve is queried every two seconds, and each point in the 
graph shows the average number of writes performed within the interval
of two seconds.  If the graph shows that an average of 5 writes per second were
performed within two seconds, Prestoserve actually performed 10
writes within those two seconds.  The calculation is:
.EX
 5 writes
---------- x 2 sec = 10 writes
   sec
.EE
.IP
If you change hosts, the 
.PN "Writes per second"
graph displays a vertical line of dashes to distinguish the new 
host's information from the previous host's information.
.IP \(bu 4
The 
.PN "Hits per second"
trend line graph shows a recent history of the average number of 
Prestoserve cache hits per second over the time intervals that 
are determined by the
.PN "Sample Interval"
slider.  The Prestoserve cache hits represent the total number of 
clean and dirty read and write hits (blocks that match blocks already
in the cache).  
.IP
Each point in the horizontal axis represents a sample time interval
as determined by the 
.PN "Sample Interval" 
slider; the maximum number of samples that can be shown is 210.  
When you reach the maximum number of samples, the graph shifts to the 
left so you can see at least the last 105 samples, which is half the
maximum number of samples.
If you choose 2 in the 
.PN "Sample Interval"
slider, Prestoserve is queried every two seconds; therefore it takes
420 (2 x 210) seconds to obtain the maximum of 210 samples.
.IP
The vertical axis shows the average number of hits performed per
second within the sample time interval as determined by the 
.PN "Sample Interval"
slider.
.IP
For example, if you choose 10 in the 
.PN "Sample Interval" 
slider, Prestoserve is queried every 10 seconds, and each point in the 
graph shows the average number of hits performed within the interval
of 10 seconds.  If the graph shows that an average of 2 hits per second were
performed within 10 seconds, Prestoserve actually performed 20
writes within those 10 seconds.  The calculation is:
.EX
  2 hits
---------- x 10 sec = 20 hits
   sec
.EE
.IP
If you change hosts, the 
.PN "Hits per second"
graph displays a vertical line of dashes to distinguish the new host's 
information from the previous host's information.
.PP
If you display the 
.PN "Display Cache Statistics"
table, the following is shown:
.IP \(bu 4
The Prestoserve statistics table is similar to the information that is
displayed when you use the 
.PN "presto \-p"
command.  For each Prestoserve cache read or write operation, Prestoserve 
increments an appropriate counter.  The table shows:
.IP
The clean hits counter, which is the number of hits on the clean
buffers
.IP
The dirty hits counter, which is the number of hits on the
dirty buffers (each dirty hit represents a physical 
disk write that was avoided entirely)
.IP
The passes counter, which is the number of I/O operations that
Prestoserve passed directly to the actual device driver
.IP
The count, which is the sum of the three previous counters
.IP
The hit rate percentage, which is the ratio of clean hits 
and dirty hits to the total count
.IP \(bu 4
The
.PN "Since last Enable"
button allows you to display Prestoserve statistics since Prestoserve
was last enabled.  This is useful when you want to determine how
Prestoserve performs over a long period of time.
.IP \(bu 4
The
.PN "Since last Sample"
button allows you to display the Prestoserve statistics for each sample
time interval as determined by the 
.PN "Sample Interval"
slider.  If no Prestoserve activity occurs during the time interval,
the numbers in the statistics table are zero.  For example, if the 
.PN "Sample Interval"
slider is set to 5 and the 
.PN "Since last Sample"
button is enabled, the statistics table shows the Prestoserve
statistics for each interval of five seconds.  
.IP \(bu 4
The 
.PN "Since last Zero"
button allows you to display Prestoserve statistics since you clicked
on the 
.PN Zero
button. This button allows you to determine how
Prestoserve performs over a specific period of time that you can set by using the 
.PN Zero
button.
.IP \(bu 4
The 
.PN Zero
button allows you to set a time reference for the Prestoserve statistics table.
If you click on the 
.PN Zero
button and, at a later time, click on the 
.PN "Since last Zero"
button, the table displays the Prestoserve statistics since you clicked on the 
.PN Zero 
button.
.SH Options
.TP 20
.B \-bd \fIcolor\fP
Specifies the color of the window's border (color displays only).
The default is black.
.TP 20
.B \-bg \fIcolor\fP
Specifies the color of the window's background (color displays only).
The default is white.
.TP 20
.B \-d \fIdispname\fP
Specifies the display screen on which 
.PN dxpresto 
displays its window.  If the
display option is not specified, 
.PN dxpresto
uses the display screen specified
by your DISPLAY environment variable.  The display option has the format
\fIhostname:number.\fP  Using two colons (::) instead of one (:) indicates that
DECnet is to be used for transport.  The default is :0.  For more information,
see 
.MS X 1X .
.TP 20
.B \-display \fIdispname\fP
This option is the same as the \fB\-d\fP option.
.TP 20
.B \-fg \fIcolor\fP
Specifies the color of the text 
(color displays only).
The default is black.
.TP 20
.B \-geometry 
Specifies the width, length, and location of
the
.PN dxpresto 
window.
If the geometry option is not specified,
.PN dxpresto 
uses default values.
The geometry option has the format
\fB=\fR[\fIwidth\fR][x\fIlength\fR][\fIx\fR][\fIy\fR].
For more information about the screen coordinate system,
see
.MS X 1X .
.SH X Defaults
The
.PN dxpresto
application uses the values in the \fB.Xdefaults\fR file when you logged in
and uses the appropriate resource specification to customize the appearance
or characteristics of its displayed
.PN dxpresto
window.
The format for a resource
specification in the \fB.Xdefaults\fP file is:
.IP "" 15
[\^\fIname\fP*\^]\^\fIresource\fR\^:  \fIvalue\fR
.IP \fIname\fR 1i
Specifies the application name or
the name string that restricts the resource assignment to
that application or to a component of an application.
If this argument is not specified,
the resource assignment is globally available to all X applications.
.IP \fIresource\fR 1i
Specifies the resource.
.IP \fIvalue\fR 1i
Specifies the value that is to be assigned to the resource.
.PP
For more information,
see
.MS X 1X .
.PP
Because each toolkit-based application can consist of a combination of
widgets (for example, push buttons and a scroll bar),
you can form the name string
by adding widget class and name identifiers
to the string.
For further information about adding class and name identifiers,
see
.MS X 1X .
.PP
For
.PN dxpresto ,
the available name identifiers are:
.IP graph_parent 20
The dialog box containing all of the graphs
.IP dirty_graph
The graph displaying dirty buffers
.IP clean_graph
The graph displaying clean buffers
.IP inval_graph
The graph displaying inval buffers
.IP active_graph
The graph displaying active buffers
.IP write_graph
The graph displaying cache write history
.IP hit_graph
The graph displaying cache hit history
.SH Examples
If you want to change the foreground and background colors of the 
.PN dxpresto
window and to customize the window's graphs, you can 
add the following entries to your \fB.Xdefaults\fP file: 
.EX
dxpresto*background:                    darkslategray
dxpresto*foreground:                    wheat
dxpresto*borderColor:                   gold
dxpresto*highlight:                     yellow
dxpresto*graph_parent*borderColor:      firebrick
dxpresto*dirty_graph*highlight:         gold
dxpresto*dirty_graph*background:        black
dxpresto*clean_graph*highlight:         gold
dxpresto*clean_graph*background:        black
dxpresto*inval_graph*highlight:         gold
dxpresto*inval_graph*background:        black
dxpresto*active_graph*highlight:        gold
dxpresto*active_graph*background:       black
dxpresto*write_graph*highlight:         gold
dxpresto*write_graph*background:        black
dxpresto*hit_graph*highlight:           gold
dxpresto*hit_graph*background:          black
.EE
.SH Files
.PN /usr/lib/X11/uid/dxpresto.uid 
.br
.PN ~/.Xdefaults
.SH See Also
presto(4),
presto(8),
prestoctl_svc(8),
X(1X)
.br
\fIGuide to Prestoserve\fP