Checking for swappers on XenServer - Revision history

Christoph at 04:49, 30 October 2013

2013-10-30T04:49:25Z

Christoph at 19:03, 25 October 2013

2013-10-25T19:03:53Z

Christoph: /* XenServer */

2013-09-05T12:42:38Z

‎XenServer

Christoph: /* XenServer */

2013-08-29T10:00:42Z

‎XenServer

Christoph: /* XenServer */

2013-08-29T09:56:21Z

‎XenServer

Christoph: /* XenClassic */

2013-08-29T07:51:34Z

‎XenClassic

Christoph: /* XenServer */

2013-08-29T05:04:06Z

‎XenServer

Christoph: /* XenServer */

2013-08-28T11:04:50Z

‎XenServer

Christoph: /* XenClassic slice configuration file */

2013-08-28T08:49:40Z

‎XenClassic slice configuration file

Christoph: /* XenServer */

2013-08-27T10:52:02Z

‎XenServer

← Older revision		Revision as of 04:49, 30 October 2013
Line 1:		Line 1:
−	This article will outline the steps I take to check for swappers on my ''XenServer'' and ''XenClassic'' setups.	+	This article will outline the steps I take to check for [[Linux swap space\|swappers]] on my ''XenServer'' and ''XenClassic'' setups.

	==''XenServer''==		==''XenServer''==

@@ Line 2: / Line 2: @@
 ==''XenServer''==
-* Log into the huddle the host in question is located in
+* Log into the host the slice/instance is located on
-* Log into the host the slice/instances is located on
 * Run <code>iostat</code> to check for any swappers on this host:
   $ iostat -xkd 1
@@ Line 25: / Line 24: @@
   $ xe vdi-list uuid=fff-fff-fff-fff-fff
   uuid ( RO)                : fff-fff-fff-fff-fff
-            name-label ( RW): slice01234
+            name-label ( RW): slice01234_swap
       name-description ( RW):
                sr-uuid ( RO): 76fa2a40-5729-1297-a4d8-38df5ea4128c
@@ Line 33: / Line 32: @@
 * Check to make sure no other tasks are currently being performed on this host (except for "pending: reboot"-like statuses):
   xe task-list
-* Now force a reboot
+* Now force a reboot:
   xe vm-reboot --force name-label=slice01234
 * Check that the slice has actually rebooted:
   xe vm-list name-label=slice01234 params=start-time
-* Verify that the output from the last command is within the current timestamp
+* Verify that the output from the last command is within the current timestamp (UTC):
-  date
+  date -u
-* As a final step, you can bring up the slices console to check for any errors, problems, or wait times (e.g., [[fsck]]ing):
+* As a final step, you can bring up the slice's console to check for any errors, problems, or wait times (e.g., [[fsck]]ing):
   xl console slice01234
-That's it! You have successfully killed a swapper and brought the slice back up to a normal load.
+That is it! You have successfully killed a swapper and brought the slice back up to a normal load.
 * The following does the same as the above (without rebooting) as a single CLI script:
@@ Line 60: / Line 59: @@
 This is how you do the above on a ''XenClassic'' setup.
-* Log into the huddle the host in question is located in
+* Log into the host the slice/instance is located on
-* Log into the host the slice/instances is located on
 * Run <code>iostat</code> to check for any swappers on this host:
   iostat -xkd 1
 * If swappers are found, list the device mapper for this slice:
   ls -l /dev/mapper/ | grep ' 20 '
-* Now "destroy" that slice (we are not permanently destroying this device, that's just the terminology):
+* Now "destroy" that slice (we are not permanently destroying this device, that is just the terminology):
   xm destroy slice01234
 * Finally, re-create this slice (this takes information from a configuration flatfile found under <code>/etc/xen/slice01234</code>):
@@ Line 73: / Line 71: @@
   xm console slice01234
-That's it! You have successfully killed a swapper and brought the slice back up to a normal load.
+That is it! You have successfully killed a swapper and brought the slice back up to a normal load.
 We can accomplish the above with a single script (well, a series of CLI calls) like so:
@@ Line 91: / Line 89: @@
   xm destroy slice01234 && xm create slice01234 && xm console slice01234
-===XenClassic slice configuration file===
+===''XenClassic'' slice configuration file===
-Below is an example of what a slice configuration flatfile (which is, by default, located at <code>/etc/xen/slice01234</code>) would look like:
+Below is an example of what a ''XenClassic'' slice configuration flatfile would look like (which is, by default, located at <code>/etc/xen/slice01234</code>):
   name="slice01234"
   memory=512

@@ Line 39: / Line 39: @@
 * Verify that the output from the last command is within the current timestamp
   date
 That's it! You have successfully killed a swapper and brought the slice back up to a normal load.

@@ Line 6: / Line 6: @@
 * Run <code>iostat</code> to check for any swappers on this host:
   $ iostat -xkd 1
 * If swappers are found, cat the device of the slice to get its minor number:
   $ cat /sys/block/tdk/dev
 :20 # this is the major:minor number of the device
 * Get the UUID for this slice
   $ tap-ctl list | grep minor=20
   # ~OR~
   $ tap-ctl list -m 20
   pid=12912 minor=20 state=0 args=vhd:/var/run/sr-mount/eee-eee-eee-eee-eee/fff-fff-fff-fff-fff.vhd
 * Check if this slice is a "swap" partition (make sure it is _not_ a root partition!):
   $ xe vdi-list uuid=fff-fff-fff-fff-fff

@@ Line 5: / Line 5: @@
 * Log into the host the slice/instances is located on
 * Run <code>iostat</code> to check for any swappers on this host:
-  iostat -xkd 1
+  $ iostat -xkd 1
 * If swappers are found, cat the device of the slice to get its minor number:
-  cat /sys/block/tdk/dev  # returns something like: 1234:20
+  $ cat /sys/block/tdk/dev
 * Get the UUID for this slice
-  tap-ctl list | grep minor=20
+  $ tap-ctl list | grep minor=20
   # ~OR~
-  tap-ctl list -m 20
+  $ tap-ctl list -m 20
 * Check if this slice is a "swap" partition (make sure it is _not_ a root partition!):
-  xe vdi-list uuid=xxxx-xxxx-xxxx-xxxx
+  $ xe vdi-list uuid=fff-fff-fff-fff-fff
 * Check to make sure no other tasks are currently being performed on this host (except for "pending: reboot"-like statuses):
   xe task-list

← Older revision		Revision as of 05:04, 29 August 2013
Line 24:		Line 24:

	That's it! You have successfully killed a swapper and brought the slice back up to a normal load.		That's it! You have successfully killed a swapper and brought the slice back up to a normal load.
		+
		+	* The following does the same as the above (without rebooting) as a single CLI script:
		+	(echo "Slice IO_Read IO_Write Total"; \
		+	(for uuid in $(xe vbd-list params=uuid \| awk '$5{print $5}'); do \
		+	xe vbd-param-list uuid=$uuid \| grep -P "^\s*(io_\|vm-name-label\|device)" \| \
		+	awk '{if($1=="vm-name-label") name=$4; \
		+	if($1=="device") {\
		+	if($4=="xvdc" \|\| $4=="xvdd") name=name"-swap"; \
		+	if($4=="xvda" \|\| $4=="xvdb") name=name"-root";} \
		+	if($1=="io_read_kbs") ioread=$4; \
		+	if($1=="io_write_kbs") iowrite=$4}\
		+	END{if(substr(name,0,9)!="XenServer") print name" "ioread" "iowrite" "ioread+iowrite}';\
		+	done) \| sort -k4n) \| column -t

	==''XenClassic''==		==''XenClassic''==

@@ Line 67: / Line 67: @@
   cpu_weight=512
   extra="xencons=tty console=tty1 clocksource=acpi_pm "
 [[Category:XenServer]]