Bug 1297255 - add possibility to sparsify image during block copy
add possibility to sparsify image during block copy
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: libvirt (Show other bugs)
Unspecified Unspecified
high Severity high
: rc
: 7.4
Assigned To: Peter Krempa
Han Han
Depends On: 1533975 1232914 1242316
Blocks: 1229843 1401400 1473733 1477664 1288337
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Reported: 2016-01-10 20:39 EST by Fam Zheng
Modified: 2018-02-27 01:51 EST (History)
23 users (show)

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Clone Of: 1232914
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Comment 24 Peter Krempa 2017-12-12 04:01:46 EST
Fixing summary to clarify. 

Description asks libvirt to add possibility to enable sparsification of the regions of the image containing only zero blocks so that they are actually unmapped.

Note that this comes with a performance penalty thus it should not be enabled by default.

Also note that qemu already keeps the unmaped regions unmapped when copying, so this is useful only when the regions were not unmapped before for some reasons.

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