Add RAID viewer.

diff --git a/2019-fosdem/nbdview/README b/2019-fosdem/nbdview/README
index ad14699..ed6bc8e 100644 (file)
--- a/2019-fosdem/nbdview/README
+++ b/2019-fosdem/nbdview/README
@@ -1,3 +1,6 @@
+nbdview
+-------
+
 nbdview is a small Tcl/Tk program that lets you visualize reads and
 writes happening to an nbdkit server in real time.
 
@@ -6,7 +9,7 @@ filter.  For example, using the memory plugin (but any plugin may be
 used):
 
   size=$((64 * 1024 * 1024))
-  delay=20ms
+  delay=40ms
   nbdkit --filter=log --filter=delay \
          memory \
          size=$size \
@@ -29,3 +32,27 @@ most 64MB.
 Then you can write to the NBD server using ordinary tools such as
 qemu, qemu-io, guestfish, etc. and observe the reads and writes to the
 disk.
+
+nbdraid
+-------
+
+As above but allowing you to display operations to multiple (RAID)
+devices.
+
+Start N copies of nbdkit like this:
+
+  size=$((64 * 1024 * 1024))
+  delay=40ms
+  rm /tmp/error$i
+  rm /tmp/sock$i
+  nbdkit -U /tmp/sock$i \
+         --filter=error --filter=log --filter=delay \
+         memory \
+         size=$size \
+         logfile=/tmp/log$i \
+         rdelay=$delay wdelay=$delay \
+         error-rate=1 error-file=/tmp/error$i &
+
+Then start nbdraid.tcl:
+
+  ./nbdraid $N $size /tmp/log%d /tmp/error%d

diff --git a/2019-fosdem/nbdview/nbdraid.tcl b/2019-fosdem/nbdview/nbdraid.tcl
new file mode 100755 (executable)
index 0000000..a6dada1
--- /dev/null
+++ b/2019-fosdem/nbdview/nbdraid.tcl
@@ -0,0 +1,118 @@
+#!/usr/bin/env wish
+# Visualize RAID activity - read the README file first!
+# Copyright (C) 2018 Red Hat Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution.
+#
+# * Neither the name of Red Hat nor the names of its contributors may be
+# used to endorse or promote products derived from this software without
+# specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+# PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
+# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+# OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+package require Tk
+
+source "nbdcanvas.tcl"
+
+set blocksize 4096
+set width 128
+set scale 2
+
+# This list is used to store all the RAID handles.
+set handles {}
+
+# This function polls the log file of each handle (every 100 ms).
+proc poll {} {
+    global handles
+
+    foreach h $handles {
+        nbdpoll $h
+    }
+    after 100 poll
+}
+
+# Parse command line.
+if { $argc != 4 } {
+    puts "usage: nbdview N size logfile-pattern errorfile-pattern"
+    exit 1
+}
+set N [lindex $argv 0]
+set size [lindex $argv 1]
+set logpattern [lindex $argv 2]
+set errorpattern [lindex $argv 3]
+
+# Menubar.
+option add *tearOff 0
+menu .menubar
+. configure -menu .menubar
+menu .menubar.file
+.menubar add cascade -menu .menubar.file -label File
+.menubar.file add command -label "Quit" -command { exit }
+
+# Frame.
+frame .f
+pack .f -anchor center -expand 1 -fill both -ipadx 10 -ipady 10
+
+# Canvases.
+for { set i 1 } { $i <= $N } { incr i } {
+    set logfile($i) [format $logpattern $i]
+    set errorfile($i) [format $errorpattern $i]
+
+    # VBox to store the canvas and controls.
+    set box ".f.h$i"
+    frame $box
+    pack $box -side left -expand 1 -fill both
+
+    # Create the error checkbox.
+    set errorbutton "$box.e"
+    set errorvar($i) off
+    checkbutton $errorbutton -text "Error" -variable errorvar($i) \
+        -command "set_errorfile $i"
+    proc set_errorfile { i } {
+        global errorvar errorfile
+        if { $errorvar($i) } {
+            # Touch the error inject file.
+            close [open $errorfile($i) "w"]
+        } else {
+            # Delete it.
+            file delete $errorfile($i)
+        }
+    }
+    pack $errorbutton -side top -anchor nw -expand 0 -fill none
+
+    # Create the i'th canvas.
+    set canvas "$box.c"
+    set h [nbdcanvas $canvas $logfile($i) $size $blocksize $width $scale]
+    $canvas configure -borderwidth 4 -relief groove
+    pack $canvas -side top -expand 0 -fill none
+
+    lappend handles $h
+}
+
+# Set up the window.
+wm title . "nbdraid"
+wm resizable . false false
+
+# Start polling the log file.
+after 100 poll