<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Sep 13, 2012, at 01:38 , Corin Langosch wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">
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<div id="smartTemplate4-template">On 12.09.2012 at 21:34 +0200, Kir
Kolyshkin <a class="moz-txt-link-rfc2396E" href="mailto:kir@openvz.org"><kir@openvz.org></a> wrote:<br>
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<blockquote cite="mid:CAGmPdryGZ8Pe3sYToGCpFnF4t672J6yC0v_vv34VBjmxgobSbQ@mail.gmail.com" type="cite"><p dir="ltr">
On Sep 12, 2012 11:20 PM, "Corin Langosch" <<a moz-do-not-send="true" href="mailto:info@corinlangosch.com">info@corinlangosch.com</a>>
wrote:<br>
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> Hi,<br>
><br>
> it seems that when creating & deleting files inside a
ploop backed container the backing image file doesn't shrink. So
the image file is still consuming around 400 GB, while in the
container df shows only 100 GB in use.<br>
><br>
> ll on host: -rw------- 1 root root 384G Sep 12 21:06
root.hdd<br>
> df on container: /dev/ploop1 493G 103G 390G
21% /</p><p dir="ltr">We have online shrink. It's "ploop balloon discard"
or just "vzctl compact". You'd better have ploop and vzctl from
git (both are really close to be released).</p>
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The system's still working heavily but the image is already reduced
by around 60 GB so it seems to work well. :)<br>
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Would you suggest putting some script into crontab to compact all
ploop images ex. once a week? Or probably do something like ctid%7
and compact a few of them every night?<br>
<br>
BTW: the man of vzctl contains the "compact" command. But the usage
output of vzctl doesn't. Shall I file a bug report for it?<br>
<br>
BTW 2: I just read about the ploop ballooning technique in the wiki.
Am I correct in that it works quite similar to sdelete on windows (
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<a href="http://pastie.org/4710364">http://pastie.org/4710364</a> or
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<a href="http://technet.microsoft.com/en-us/sysinternals/bb897443.aspx">http://technet.microsoft.com/en-us/sysinternals/bb897443.aspx</a>)?<br></div></blockquote></div><br><div>No, AFAIR we should use TRIM on ext4 and it simply reports unused space.</div><div>Balloon is used for "resize" via allocating some space and hiding it from user, but for compacting it's a bit bad since can cause ENOSPC while it's really not...</div><div><br></div><div>Kirill</div><div><br></div></body></html>