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Am Sun, Apr 03, 2022 at 05:05:07PM +0100 schrieb Wol: |
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> > > > Rsync has a bwlimit argument which helps here. Note that rsync copies |
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> > > > the whole file on what it considers local storage (which can be mounted |
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> > > > network shares) ... this can cause a real slowdown. |
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> > > It won't help on the initial copy, but look at the - I think it is - |
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> > > --in-place option. |
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> |
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> > This one is mostly useful if space on the destination is tight or the data |
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> > link (for FS commands) is slooow, because normally rsync creates a new temp |
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> > file and moves it into place once the transfer is complete. |
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> And making a temporary file may be exactly what you DON'T want. I make heavy |
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> use of hard links, |
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… which the -H option is for. |
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> and "make a temp file" absolutely buggers file system integrity ... |
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Can you elaborate? A temp file is just like any other file. If you do |
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in-place syncing, then it “buggers up” the original file instead of a temp. |
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> And my use case with LVM and backups, "make a temp file" does both |
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> absolutely nothing to protect file system integrity |
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I was not actually talking about file *system* integrity, but that if you |
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overwrite in-place and the connection is lost during transfer, you are left |
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with an incomplete file. Hence you just lost data on the destination. The FS |
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itself is not adversely affected by that, only the file. |
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> and makes every backup waste far more space than is necessary ... |
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How so? If it’s a COW filesystem, I can understand it (insofar as if you do |
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in-place, then the existing file is deleted first, which gives the FS more |
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space for the new copy). |
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> So --in-place actually has a lot of uses outside your two examples. I have |
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> oodles of space, and both my source and target are on fast sata links in the |
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> same computer, but not using --in-place would be *very* costly for me. |
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Well I admit I don’t know much outside of my realm of local disks with ext4, |
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zfs and ssh. While I do run LVM on my laptop, it’s just so that I can have |
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“partitions” on an otherwise fully encrypted block device. I never used any |
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of its more fancy features. |
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-- |
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Grüße | Greetings | Salut | Qapla’ |
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Please do not share anything from, with or about me on any social network. |
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Grammar: the difference between knowing your shit and knowing you’re shit. |
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