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Olaf Hering
6728b4d422
Write up some sparse documentation about xenpaging usage. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
49 lines
1.4 KiB
Plaintext
49 lines
1.4 KiB
Plaintext
Warning:
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The xenpaging code is new and not fully debugged.
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Usage of xenpaging can crash Xen or cause severe data corruption in the
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guest memory and its filesystems!
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Description:
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xenpaging writes memory pages of a given guest to a file and moves the
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pages back to the pool of available memory. Once the guests wants to
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access the paged-out memory, the page is read from disk and placed into
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memory. This allows the sum of all running guests to use more memory
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than physically available on the host.
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Usage:
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Once the guest is running, run xenpaging with the guest_id and the
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number of pages to page-out:
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chdir /var/lib/xen/xenpaging
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xenpaging <guest_id> <number_of_pages>
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To obtain the guest_id, run 'xm list'.
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xenpaging will write the pagefile to the current directory.
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Example with 128MB pagefile on guest 1:
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xenpaging 1 32768
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Caution: stopping xenpaging manually will cause the guest to stall or
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crash because the paged-out memory is not written back into the guest!
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After a reboot of a guest, its guest_id changes, the current xenpaging
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binary has no target anymore. To automate restarting of xenpaging after
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guest reboot, specify the number if pages in the guest configuration
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file /etc/xen/vm/<guest_name>:
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xenpaging=32768
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Redo the guest with 'xm create /etc/xen/vm/<guest_name>' to activate the
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changes.
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Todo:
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- implement stopping of xenpaging
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- implement/test live migration
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# vim: tw=72
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