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* Joakim Tjernlund <joakim.tjernlund@×××××××××.se> [120124 02:18]: |
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> Ed W <lists@××××××××××.com> wrote on 2012/01/23 19:43:49: |
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[ .. ] |
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> > I'm doing something like this using aufs. The performance seems "not |
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> > bad", but you get a couple MB or so memory hit. (I'm using squashfs as |
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> > well, so unsure which causes the main memory increase). |
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> |
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> hmm, not sure how aufs would work out. One would like to permanently delete the |
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aufs is A Union FileSystem. You can have a RO "branch" (say SquashFS) |
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and a r/w "branch" (say JFFS2 or UBIFS.) When you write it will write |
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to the r/w branch and when you read it will read from the r/w branch if |
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it exists, else the r/o. |
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So, if you want to permanently delete the old software. Write it to the |
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filesystem r/w filesystem (initially or after you have the aufs mounts |
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mounted.) Then you can delete from the r/w filesystem and it's gone for |
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good. |
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> old sw at some point and I don't see how, perhaps I misunderstand something? |
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> |
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> How does aufs do w.r.t power cuts? We need a reliable FS w.r.t power cuts. In the |
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> past we have used JFFS2 on NOR flash and that has worked really well. Now |
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> we need to switch to NAND due to size requirements. |
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You still want to pick a r/w branch with a filesystem that handles power |
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cuts well. You can continue to use JFFS2. |
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[..] |
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Todd |