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On 2017-05-24 19:05, Kai Krakow wrote: |
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> To get in line with Rich Freeman: I didn't want to imply that zswap |
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> only works with swap, neither that tmpfs only works with swap. Both |
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> work without. But if you want to put some serious amount of data into |
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> tmpfs, you need swap as a backing device sooner or later. |
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Looking at zswap, I have several questions |
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(even after reading linux/Documentation/vm/zswap.txt). |
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1. How does it know which swap device to use as backing store, if any? |
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Clearly at boot time no swap configuration exists, even if |
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initrd/initramfs is used, which here it is not. So when the kernel sees |
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zswap.enable=1 in the command line, what happens? |
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2. The doc says it can be turned on at runtime by means of |
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/sys/module/zswap/parameters/enabled. But kconfig doesn't make it |
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possible to build the support as a module, only built-in, and so it is |
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not surprising that this path doesn't exist. |
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3. It seems to require zbud to also be turned on, but this is not |
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enforced by kconfig. Is this a bug or what? |
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4. Quoting: |
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Zswap seeks to be simple in its policies. Sysfs attributes allow for one user |
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controlled policy: |
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* max_pool_percent - The maximum percentage of memory that the compressed |
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pool can occupy. |
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Does this mean this is another (hypothetical) node in |
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/sys/module/zswap/parameters/ ? |
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-- |
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http://primate.net/~itz/blog/the-problem-with-gpg-signatures.html |
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