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awarded  Yearling
Apr
1
answered What is a socket?
Mar
22
comment Do I need swap space if I have more than enough amount of RAM?
@RemcoGerlich: It's not that a computer with 16GB RAM and no swap has any trouble running fine. It's that a computer with 16GB RAM and swap runs better. Swap does not cost you anything (well, an insignificant portion of your harddisk, but that hardly counts), but it allows you to make better use of the available RAM for the stuff that matters by paging the stuff that isn't needed out.
Mar
20
revised Do I need swap space if I have more than enough amount of RAM?
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Mar
17
awarded  Mortarboard
Mar
17
awarded  Good Answer
Mar
16
awarded  Nice Answer
Mar
16
comment Do I need swap space if I have more than enough amount of RAM?
The reason why I advocate a comparatively small swap (half a gigabyte) is precisely that swap is not meant to turn 16GiB into 32GiB -- this would indeed cause things to come to a crawl. It's meant to swap out a few things that aren't needed right now, which is usually a few dozen megabytes or less (so 512 MiB is plenty more than you'll need). Actually using several gigabytes of swap is a severely unhealthy condition. If you have 64GiB of live data to deal with, you need 64GiB of RAM, throwing swap at the problem is the wrong way.
Mar
16
awarded  Commentator
Mar
16
comment Do I need swap space if I have more than enough amount of RAM?
... when you switch to a different desktop, the system can swap out the terminal and you will not notice a difference at all. If you have a dozen programs open, the OS can (it does not need to, but it can) swap out the program you're not using. It will take 50-100 milliseconds to swap it in again at a later time, but you will usually hardly notice that this is happening. Overall, it is a huge improvement, since you effectively have more RAM available for the stuff you use, when you're using it.
Mar
16
comment Do I need swap space if I have more than enough amount of RAM?
@mikeserv: You have an opinion ("completely untrue!") which is debatable and contrary to the opinon of noteworthy experts, yet you are of course entitled to that opinion. Also, you make a lot of assumptions that are not true. For example, reloading from the original is simply not possible for data that has no "original" backed by a file. Also, the system does not slow to a crawl when swapping occurs, this only happens when you have an active dataset of considerable size (as I've pointed out in the answer). Under normal conditions, swapping will be hardly noticeable, if at all, for example...
Mar
16
comment Do I need swap space if I have more than enough amount of RAM?
@Mehrdad: It certainly does make sense. Slower memory (swap) improves performance insofar as "slower" does not matter for things that you access rarely or never. Swap effectively increases the amount of memory that is available for "hot" data by moving "cold" data out. Daemons which only execute something once per hour or memory allocated by a kernel module that is loaded by default but never used are an example of that. You can swap out those, or you can instead drop pages from the cache. Which one is better?
Mar
16
awarded  Yearling
Mar
16
answered Do I need swap space if I have more than enough amount of RAM?
Jan
29
awarded  Nice Answer
Jan
28
comment Any disk encryption that locks itself for some time after a number of failed attempts?
Hehehe, the --iter-time=600000 suggestion is a funny solution. Good one :-)
Jan
28
comment Any disk encryption that locks itself for some time after a number of failed attempts?
About controlling the unlock frequency as you call it, the problem is that the attacker will not go through that door at all. You can prevent your 5-year old sister from typing in one password after another, but you cannot prevent someone from reading a raw sector and trying a thousand passwords (or, well, millions or billions, depending on how complicated/easy the key derivation algo is) per second on a dedicated massively parallel machine.
Jan
28
comment Any disk encryption that locks itself for some time after a number of failed attempts?
An assumed random case-sensitive-alphanumeric 8-character password would have slightly less than 48 bits, which will be enough to hold back an attacker for a good while, if a good key derivation algorithm is used (one that takes, say, half a second). But of course random case-sensitive-alphanumeric means it's a pain to remember and to type again (unless you make it "not really random", at which point it's useless).
Jan
28
awarded  Editor
Jan
28
awarded  Yearling