Domain ID/index mapping in xenmon.

This patch addresses the problem of xenbaked/xenmon not dealing with
large domain ID's. Xen Domain ID's increase monotonically as domains
are created; The ID's are not (often) recycled. Xenbaked was using the 
domain
ID's as indices to arrays of data, and this scheme blows up as soon as
a domain ID exceeds the array size. Code has been changed in xenbaked
and xenmon to isolate domain id's from array indices, so everything is
indirect. Users should not notice any difference in behavior.

From: Rob Gardner <rob.gardner@hp.com>
Signed-off-by: Keir Fraser <keir@xensource.com>

1 files changed, 33 insertions, 19 deletions

diff --git a/tools/xenmon/xenmon.py b/tools/xenmon/xenmon.py
index c8e2babe2f..1b74d19403 100644
--- a/tools/xenmon/xenmon.py
+++ b/tools/xenmon/xenmon.py
@@ -36,10 +36,10 @@ import sys
 # constants
 NSAMPLES = 100
 NDOMAINS = 32
-IDLE_DOMAIN = 31 # idle domain's ID
+IDLE_DOMAIN = -1 # idle domain's ID
 
 # the struct strings for qos_info
-ST_DOM_INFO = "6Q4i32s"
+ST_DOM_INFO = "6Q3i2H32s"
 ST_QDATA = "%dQ" % (6*NDOMAINS + 4)
 
 # size of mmaped file
@@ -297,6 +297,7 @@ def show_livestats(cpu):
             samples = []
             doms = []
             dom_in_use = []
+            domain_id = []
 
             # read in data
             for i in range(0, NSAMPLES):
@@ -311,9 +312,13 @@ def show_livestats(cpu):
                 doms.append(dom)
 #		(last_update_time, start_time, runnable_start_time, blocked_start_time,
 #		 ns_since_boot, ns_oncpu_since_boot, runnable_at_last_update,
-#		 runnable, in_use, domid, name) = dom
+#		 runnable, in_use, domid, junk, name) = dom
 #		dom_in_use.append(in_use)
                 dom_in_use.append(dom[8])
+                domid = dom[9]
+                if domid == 32767 :
+                    domid = IDLE_DOMAIN
+                domain_id.append(domid)
                 idx += len
 #            print "dom_in_use(cpu=%d): " % cpuidx, dom_in_use
 
@@ -366,16 +371,16 @@ def show_livestats(cpu):
             if not dom_in_use[dom]:
                 continue
 
-            if h1[dom][0][1] > 0 or dom == NDOMAINS - 1:
+            if h1[dom][0][1] > 0 or domain_id[dom] == IDLE_DOMAIN:
                 # display gotten
                 row += 1 
                 col = 2
-                display_domain_id(stdscr, row, col, dom)
+                display_domain_id(stdscr, row, col, domain_id[dom])
                 col += 4
                 display(stdscr, row, col, "%s" % time_scale(h2[dom][0][0]))
                 col += 12
                 display(stdscr, row, col, "%3.2f%%" % h2[dom][0][1])
-                if dom != NDOMAINS - 1:
+                if dom != IDLE_DOMAIN:
                     cpu_10sec_usage += h2[dom][0][1]
                 col += 12
                 display(stdscr, row, col, "%s/ex" % time_scale(h2[dom][0][2]))
@@ -388,14 +393,14 @@ def show_livestats(cpu):
                 col += 18
                 display(stdscr, row, col, "Gotten")
 
-                if dom != NDOMAINS - 1:
+                if dom != IDLE_DOMAIN:
                     cpu_1sec_usage = cpu_1sec_usage + h1[dom][0][1]
     
                 # display allocated
                 if options.allocated:
                     row += 1
                     col = 2
-                    display_domain_id(stdscr, row, col, dom)
+                    display_domain_id(stdscr, row, col, domain_id[dom])
                     col += 28
                     display(stdscr, row, col, "%s/ex" % time_scale(h2[dom][1]))
                     col += 42
@@ -407,7 +412,7 @@ def show_livestats(cpu):
                 if options.blocked:
                     row += 1
                     col = 2
-                    display_domain_id(stdscr, row, col, dom)
+                    display_domain_id(stdscr, row, col, domain_id[dom])
                     col += 4
                     display(stdscr, row, col, "%s" % time_scale(h2[dom][2][0]))
                     col += 12
@@ -427,7 +432,7 @@ def show_livestats(cpu):
                 if options.waited:
                     row += 1
                     col = 2
-                    display_domain_id(stdscr, row, col, dom)
+                    display_domain_id(stdscr, row, col, domain_id[dom])
                     col += 4
                     display(stdscr, row, col, "%s" % time_scale(h2[dom][3][0]))
                     col += 12
@@ -447,7 +452,7 @@ def show_livestats(cpu):
                 if options.excount:
                     row += 1
                     col = 2
-                    display_domain_id(stdscr, row, col, dom)
+                    display_domain_id(stdscr, row, col, domain_id[dom])
                     
                     col += 28
                     display(stdscr, row, col, "%d/s" % h2[dom][4])
@@ -460,7 +465,7 @@ def show_livestats(cpu):
                 if options.iocount:
                     row += 1
                     col = 2
-                    display_domain_id(stdscr, row, col, dom)
+                    display_domain_id(stdscr, row, col, domain_id[dom])
                     col += 4
                     display(stdscr, row, col, "%d/s" % h2[dom][5][0])
                     col += 24
@@ -544,6 +549,9 @@ class Delayed(file):
             self.file.write(self.delay_data)
 	self.file.write(str)
 
+    def rename(self, name):
+        self.filename = name
+
     def flush(self):
         if  self.opened:
             self.file.flush()
@@ -567,10 +575,7 @@ def writelog():
     curr = last = time.time()
     outfiles = {}
     for dom in range(0, NDOMAINS):
-        if dom == IDLE_DOMAIN:
-            outfiles[dom] = Delayed("%s-idle.log" % options.prefix, 'w')
-        else:
-            outfiles[dom] = Delayed("%s-dom%d.log" % (options.prefix, dom), 'w')
+        outfiles[dom] = Delayed("%s-dom%d.log" % (options.prefix, dom), 'w')
         outfiles[dom].delayed_write("# passed cpu dom cpu(tot) cpu(%) cpu/ex allocated/ex blocked(tot) blocked(%) blocked/io waited(tot) waited(%) waited/ex ex/s io(tot) io/ex\n")
 
     while options.duration == 0 or interval < (options.duration * 1000):
@@ -582,6 +587,7 @@ def writelog():
             samples = []
             doms = []
             dom_in_use = []
+            domain_id = []
 
             for i in range(0, NSAMPLES):
                 len = struct.calcsize(ST_QDATA)
@@ -595,8 +601,16 @@ def writelog():
 #                doms.append(dom)
 #		(last_update_time, start_time, runnable_start_time, blocked_start_time,
 #		 ns_since_boot, ns_oncpu_since_boot, runnable_at_last_update,
-#		 runnable, in_use, domid, name) = dom
+#		 runnable, in_use, domid, junk, name) = dom
                 dom_in_use.append(dom[8])
+                domid = dom[9]
+                if domid == 32767:
+                    domid = IDLE_DOMAIN
+                domain_id.append(domid)
+                if domid == IDLE_DOMAIN:
+                    outfiles[i].rename("%s-idle.log" % options.prefix)
+                else:
+                    outfiles[i].rename("%s-dom%d.log" % (options.prefix, domid))
                 idx += len
 
             len = struct.calcsize("4i")
@@ -617,9 +631,9 @@ def writelog():
             for dom in range(0, NDOMAINS):
                 if not dom_in_use[dom]:
                     continue
-                if h1[dom][0][1] > 0 or dom == NDOMAINS - 1:
+                if h1[dom][0][1] > 0 or dom == IDLE_DOMAIN:
                     outfiles[dom].write("%.3f %d %d %.3f %.3f %.3f %.3f %.3f %.3f %.3f %.3f %.3f %.3f %.3f %.3f %.3f\n" %
-                                     (interval, cpuidx, dom,
+                                     (interval, cpuidx, domain_id[dom],
                                      h1[dom][0][0], h1[dom][0][1], h1[dom][0][2],
                                      h1[dom][1],
                                      h1[dom][2][0], h1[dom][2][1], h1[dom][2][2],