1341MB swap in use with half gig of free memory

[Mark Millard]

On 2020-Jul-3, at 21:37, bob prohaska <fbsd at www.zefox.net> wrote:

> On Sat, Jul 04, 2020 at 12:22:18PM +1000, Peter Jeremy wrote:
>> Something I missed before: When you say "Pi3", I presume you mean
>> Raspberry Pi 3 Model B.  None of the Raspberry Pi variants have
>> provision for sanely attaching mass storage so I presume your 1TB
>> HDD is attached via USB 2.0 - which is a further impediment to
>> tranferring data fast.
>> 
> 
> Alas, little about my enterprise is sane 8-) These experiments
> are all on a Pi3B (not plus). The HDD is attached via a jmicron
> usb-sata adapter. 
> 
> However, the Pi4 at least in principle claims to support UASP.
> Unfortunately, it seems FreeBSD does not. That is a pity. 

Even with umass/non-UASP, USB3 can transfer much faster than USB2.

>> On 2020-Jul-03 18:15:58 -0700, bob prohaska <fbsd at www.zefox.net> wrote:
>>> On Sat, Jul 04, 2020 at 09:39:38AM +1000, Peter Jeremy wrote:
>> 
>> As Mark mentions, about the only real way to find out would be to
>> actually try building with different -j options and see which is
>> fastest.  So long as the total working set size remains below the ~800MB
>> usable RAM limit then more cores will speed it up.  Once the system
>> starts thrashing then goodput[1] drops to roughly zero.  Unfortunately,
>> the working set size varies widely.
>> 
> Up to now I've only restricted -j values when trying to avert panics.
> Perhaps the experiment is worth a try even if nothing else goes wrong.
> 
> Have you a notion whether adding additonal swap on microSD would do
> any good?

Unlikely. You need to avoid paging I/O, not use a possibly even
slower I/O mechanism. I'm not aware of the RPi3 having any likely
"dual I/O channels" based improvement of note.

> Earlier experiments included it. This one omitted it by
> chance, never expecting the build to get this far. Knowing what to
> look for is helpful.

From what I know of your past with microsd card based swap, it would
not suggest the alternative.

>>> A smaller browser would be a very welcome discovery. So far, chromium
>>> is the only one that has worked well enough to be useful.
>> 
>> If you just want to render HTML, images and some trivial JS, then
>> something like links might do.  Unfortunately, the modern Web has
>> shifted to the point where the HTML is irrelevant and the actual
>> content is mostly the result of executing quite complex JS within
>> the browser - for those pages, you'll probably need Chrom{e,ium},
>> Edge, Firefox or Safari.
> 
> It appears that links is a close relative of lynx. Both seem to
> work at www.freebsd.org, but the loss of layout information makes
> both rather hard to use. 
> 
> Firefox isn't much more compact than chromium, is Safari good anywhere
> but on a Mac? 
> 
> Edge is new to me. It shows up as /usr/ports/games/edge, but I don't
> think that's what you meant.... Any hints?
> 

Edge is Microsoft's. Windows 10, 8.1, 8, 7; iOS, Android.
(iOS might include iPadOS?) There is a legacy version as well.

Edge is Chromium based. See the 1st paragraph of:

https://docs.microsoft.com/en-us/microsoft-edge/devtools-guide-chromium


===
Mark Millard
marklmi at yahoo.com
( dsl-only.net went
away in early 2018-Mar)