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On Wednesday 25 May 2011 10:31:19 Paul Hartman wrote: |
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> When I move the swap to a slow SD card instead (2MB/sec transfer |
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> rate), even in that slow device, swapoff on the eMMC swap partition |
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> with ~500M in-use takes about 2 or 3 minutes at most with the data |
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> being swapped slowly into the SD card. |
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> |
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> So I think in your case it should be much faster than that! |
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you are comparing apples with oranges (harddisks with moving arms with solid |
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state devices). |
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Do yourself a favour. Look up how long a harddisk needs to position its head. |
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Now you can calculate how many times a second a harddisk can position its |
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head. |
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Now remember: swap is stupid, so lots and lots of head movement needed (and a |
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cash flush is running too - so even more movements to write all that crap to |
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disk), |
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The result: the whole mess is fscking slow. |
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You can have a nice fat raid with nice and fast harddisks - if you try to |
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stream to a 15 year old DLT drive with 5/10mb/sec speed the dlt drive will |
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constantly rewind - because harddisks suck when they have to seek. And swap |
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(just like a backup) = lots and lots and lots of seeks. |
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