Usage scenarios - Revision history

Dsafonov: Another crazy idea (dima)

2018-09-11T22:49:23Z

Another crazy idea (dima)

Xemul at 12:57, 13 July 2017

2017-07-13T12:57:46Z

Xemul at 18:49, 15 September 2016

2016-09-15T18:49:48Z

Kir: remove links from headers

2016-09-08T23:36:21Z

remove links from headers

Xemul: /* Slow-boot services speed up */

2015-03-19T17:41:54Z

Slow-boot services speed up

Xemul: + update dryrun

2015-03-09T19:11:58Z

+ update dryrun

Xemul: /* Snapshots of apps */

2015-03-09T19:10:49Z

Snapshots of apps

Xemul: /* Desktop environment suspend/resume */

2015-02-24T18:29:32Z

Desktop environment suspend/resume

Xemul: /* Desktop environment suspend/resume */

2015-02-24T18:28:42Z

Desktop environment suspend/resume

Xemul: /* Reboot-less kernel upgrade */

2015-02-24T18:18:57Z

Reboot-less kernel upgrade

@@ Line 74: / Line 74: @@
 Before updating a kernel/system libs one may duplicate a system service(s) into VM with updates and check they continue to run OK. If this test passes, then the real system update can be done.
 [[Category:Using]]
 [[Category:Editor help needed]]

← Older revision		Revision as of 12:57, 13 July 2017
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	[[Category:Using]]		[[Category:Using]]
		+	[[Category:Editor help needed]]

← Older revision		Revision as of 18:49, 15 September 2016
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	Before updating a kernel/system libs one may duplicate a system service(s) into VM with updates and check they continue to run OK. If this test passes, then the real system update can be done.		Before updating a kernel/system libs one may duplicate a system service(s) into VM with updates and check they continue to run OK. If this test passes, then the real system update can be done.
		+
		+	[[Category:Using]]

@@ Line 1: / Line 1: @@
-This is a set of ideas how criu can be used
+This is a set of ideas how criu can be used.
-== Container [[:Category:live migration|live migration]] ==
+== Container live migration ==
-This is the use case from what the whole checkpoint/restore project appeared. Container is checkpointed, then the image is copied on another box, then restored. From the remote observer point of view the container is just frozen for a while. You can find more details on this scenario [[LXC | here]].
+This is the use case from what the whole checkpoint/restore project appeared. Container is checkpointed, then the image is copied on another box, then restored. From the remote observer point of view the container is just frozen for a while.
-== [[Slow-boot services speed up]] ==
+''For more info, see [[:Category:live migration]].''
 If some service starts up too long (it can perform complex state initialization for example) we can checkpoint it after it finishes starting up and on the 2nd and subsequent starts restore it from the image.
@@ Line 11: / Line 13: @@
 We have a rough preliminary measurement, showing that VNC server + eclipse start time reduces from ~29 seconds to ~1.5.
-== [[Seamless kernel upgrade]] ==
+''Main article: [[slow-boot services speed up]].''
 When replacing a kernel on a box we can do it without stopping critical activity. Checkpoint it, then replace the kernel (e.g. using kexec) then restore services back. In a perfect world the applications memory shouldn't be put to disk image, but should rather be kept in RAM.
 == Networking load balancing ==
-Not the whole project, but the [[TCP_connection|TCP repair]] can be used to offload an app-level request handling on another box.
+Not the whole project, but the [[TCP connection|TCP repair]] can be used to offload an app-level request handling on another box.
 == HPC issues ==
@@ Line 26: / Line 32: @@
 # Periodic state save to avoid recomputation in case of a cluster crash. Take server snapshot every few minutes and put on other machine. When doing failover resurrect the other side quickly.
-== [[X applications|Desktop environment]] suspend/resume ==
+== Desktop environment suspend/resume ==
 Suspending a screen session and restoring it on another box might be interesting.
 Suspending some X app (browser?) and restoring it later is also worth thinking about but requires knowledge of X-protocol.
 == Processes duplication ==
@@ Line 39: / Line 47: @@
 Some arcades require you to complete next level to "fixup" the progress. With criu it can be done at any point.
-== [[Incremental dumps|Snapshots]] of apps ==
+== Snapshots of apps ==
 With CRIU one can save a series of app's states (all but first incremental) and revert later to any of them. The "apply-images" item from TODO list should help to revert the state faster, especially if the memory changes tracker state is with us.
 One of examples when this snapshot might be useful is debugging. One might need to bring an application into a "desired" state fast, and having dump at that state would speed things up.
 == Move "forgotten" applications into "screen" ==
@@ Line 59: / Line 69: @@
 == Fault-tolerant systems ==
-With CRIU it's possible to periodically duplicate process on another box. Requires [[Applying images]] facility.
+With CRIU it's possible to periodically duplicate process on another box. Requires [[applying images]] facility.
 == Update dryrun ==
 Before updating a kernel/system libs one may duplicate a system service(s) into VM with updates and check they continue to run OK. If this test passes, then the real system update can be done.

@@ Line 5: / Line 5: @@
 This is the use case from what the whole checkpoint/restore project appeared. Container is checkpointed, then the image is copied on another box, then restored. From the remote observer point of view the container is just frozen for a while. You can find more details on this scenario [[LXC | here]].
-== Slow-boot services speed up ==
+== [[Slow-boot services speed up]] ==
 If some service starts up too long (it can perform complex state initialization for example) we can checkpoint it after it finishes starting up and on the 2nd and subsequent starts restore it from the image.

← Older revision		Revision as of 19:11, 9 March 2015
Line 60:		Line 60:

	With CRIU it's possible to periodically duplicate process on another box. Requires [[Applying images]] facility.		With CRIU it's possible to periodically duplicate process on another box. Requires [[Applying images]] facility.
		+
		+	== Update dryrun ==
		+
		+	Before updating a kernel/system libs one may duplicate a system service(s) into VM with updates and check they continue to run OK. If this test passes, then the real system update can be done.