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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
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
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?
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).
Aug
26
comment How can I set up Apache to use port 1 and other ports below 80?
@MD-Tech: Note that I am not advocating the "clandestine" use of reserved ports (this means confusing people which is never good, and there remain enough "legitimate" numbers you could use). But for the most part, it's "harmless" because nobody is seriously using these anyway, and if someone is indeed, you won't notice.
Aug
26
comment How can I set up Apache to use port 1 and other ports below 80?
@MD-Tech: With a grain of salt, though. A considerable range of the reserved ports is ancient cruft and total bullshit from a current day perspective. Such as e.g. port 1 TCP which the OP was trying to use, referring to a protocol exclusively used by an operating system for SGI workstations with the last release in 1998, the last maintenance update around 2005, and currently being in "officially retired" state according to the vendor. Nobody is seriously using ports 3 to 10, 13 is obsolete, 17 is useless, 11 and 19 are not used anywhere because they're built-in exploit features, etc etc.
Feb
21
comment I deleted /bin/rm. How do I recover it?
@liori: I was half-joking, though 10-15 years ago, I would probably indeed have done it in that situation (the added "features", in particular i18n, are not an advantage in my opinion -- unintellegible translations, and learning to use switches that unexpectedly break scripts on another computer, no thanks). However, nowadays, I'm happy if only a Linux system runs smoothly as-installed without me touching anything, and without having to move/delete/edit system/config files or binaries. Which sadly, still isn't the case often enough, so I'm surely not touching something that works :-)
Feb
20
comment I deleted /bin/rm. How do I recover it?
Indeed. Actually, this makes me think about deleting coreutils too... :-)
Aug
29
comment Disable changelogs
Setting the debconf priority (I didn't even know this one existed!) alone makes it go silent, thank you. That's probably the best thing to have, too. "critical" is probably something I would want to know, and otherwise it's silent, which is just as it should be.