Erik Josefsson:
>
> As far as I understand, it is quite recent that SD cards are fast and large
> enough to be able to carry and run an entire Debian instance.
The capacity is not a problem for quite some time, depending on your
space requirements. You can still run a minimal Debian on way less than
1GB. The same is true for the speed. SD cards tend to be used with and
optimized for large(ish) files like photos and videos. Reading and
writing these files should be quite fast, but I would not expect great
performance for random I/O on small files.
> If this is the case, maybe there is only theory available regarding whether
> you can make a computer "run faster" on a 64GB SD card than on a 32GB SD
> card when cards are otherwise identical.
I don't know.
> I don't really know how swap works on a standard computer, even less how it
> works when the whole computer runs from/on a SD card.
The same as with other storage. Swap means using persistent, slow and
cheap storage as RAM. It is exactly that, cheap and painfully slow.
Under normal circumstances you should avoid swapping like the plague.
(Yes, the Linux kernel tends to make use of swap in the background "just
in case". It does not need necessarily to worry you if free(1) or top(1)
report swap usage.)
> Swap is supposed to be make your computer pretend that you have more RAM
> than it actually has, but if the whole computer is running from/on RAM (or
> is it?), then what does swap mean?
What do you mean, running from RAM? I do not see a connection of this
sentence with your previous questions about SD cards. In any case,
swapping to SD card may be even worse than swapping to traditional hard
disks.
> On Teres-I with redpill RC2 (now there is a RC3 that I have not yet
> installed) an unfortunate website with pop up commercials (like dn.se) can
> eat all performance there is and freeze the mouse for hours. I would guess
> that could have been fixed on a normal computer with "more RAM", i.e., "more
> swap"? But is the same true for e.g. Teres-I?
I don't know that hardware except for what I was able to google quickly.
But "more RAM" and "more swap" are very different things. Swap does not
help your computer to perform better. It helps your computer to do
things very, very slowly that it otherwise would not be able to do at
all.
> Second question is if it is meaningful to buy a "super duper blazing fast"
> SD card for the task to run a whole Debian system?
>
> There is a very expensive 64GB SD card from SanDisk that is called Extreme
> Pro that costs twice as much as same size Extreme Plus. Specs say it is
> "super duper blazing fast" for video in "Ultra HD 4K", but would Pro also be
> faster than Plus for the task of running Thunderbird and Firefox at the same
> time?
Not necessarily. I would try to look for benchmarks that also test
random I/O. Also, it sounds more like your system is memory-constrained
and even the fastest SD cards will not help you with that, see above.
J.
--
I think the environment will be okay.
[Agree] [Disagree]
<http://archive.slowlydownward.com/NODATA/data_enter2.html>
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