Puppy again, but wait... there's more!

[GJones]

Maybe it's the services. Lucid Puppy has ~40 tasks running on the default desktop, using about 45 MB of RAM - a lot less in both departments than most Linuxes. With three Firefox tabs open the memory usage goes only up to about 90 MB though, which still seems quite unusually low. Usually Firefox eats up more than that, I think.

I have looked into compile options... The T2 based puppy spins seem to use -fomit-frame-pointer by default, which might make a big difference. But Lucid's binaries are all derived from Ubuntu, except for the kernel.

Hmm. Maybe they've run strip on all the userspace binaries? Or is that standard distro practice? (I think Arch Linux may do it, not sure.)

[Shador]

Hmm. Maybe they've run strip on all the userspace binaries? Or is that standard distro practice? (I think Arch Linux may do it, not sure.)

We do it too and I'm fairly certain that this should only affect initial startup time and memory usage of an application, not speed. (Unless of course you run out of memory, which would cause swapping and unused cpu cycles and thus slow response.

[gapan]

Puppy runs entirely in RAM. That's the main reason it's faster. And it can run entirely in RAM, because the included applications are completely stripped down.

[Shador]

Puppy runs entirely in RAM. That's the main reason it's faster. And it can run entirely in RAM, because the included applications are completely stripped down.

But that shouldn't be much different for any linux system, if you have sufficient RAM for the core system and your applications binaries. Initial startups might be slow due to many initial disk accesses, but afterwards everything is cached by the kernel and accessed almost immediately.
Puppy probably has the advantage that it's much more trimmed down and so fits more easily into RAM. The initial loading is just moved to the booting stage so the boot is slower than when Puppy weren't loaded into RAM.

[gapan]

Exactly. By loading everything to RAM on bootup, everything launches incredibly fast, even the first time.

[GJones]

Is that the case even with the full (decompressed) hard drive install? Hmm.

(Puppy seems to refuse to copy itself to RAM when I boot the CD on the Thinkpad though - doesn't say anything about copying to RAM, and the CD won't eject while it's running. With my netbook it prints something about copying the squashfs image to RAM, and lets me eject the CD.)

Huh, wait, here's something! Xorg runs with a default niceness of -1 on Puppy. Maybe that makes a difference on old machines.

Edit: also, htop on other distros shows processes as having priorities mostly of 1 through 7... On Puppy everything (including X) has a priority of 16 to 20. Which, I think, indicates much lower priority scheduling. Weird.

[gapan]

Is that the case even with the full (decompressed) hard drive install? Hmm.

I don't know for sure, but I'm guessing it isn't.

Huh, wait, here's something! Xorg runs with a default niceness of -1 on Puppy. Maybe that makes a difference on old machines.

Edit: also, htop on other distros shows processes as having priorities mostly of 1 through 7... On Puppy everything (including X) has a priority of 16 to 20. Which, I think, indicates much lower priority scheduling. Weird.

Those shouldn't make a difference.

[Shador]

Is that the case even with the full (decompressed) hard drive install? Hmm.

I don't know for sure, but I'm guessing it isn't.

Puppy is probably still very small on such an install. So I guess it might not need to resort (so much) to swapping on low-memory machines.

[GJones]

Oh wait... Are you guys saying that, since Linux maintains a filesystem cache in RAM, a smaller Linux OS will run faster because more of it will be cached?

That makes a lot of sense actually. Puppy is smaller than just about everything else out there except Slitaz and Alpine.

[Shador]

Oh wait... Are you guys saying that, since Linux maintains a filesystem cache in RAM, a smaller Linux OS will run faster because more of it will be cached?

Yes, possibly, but only if you have few memory. With like at least 2GB of memory, everything you usually need is cached pretty soon/after first time use or access.

The one most common slow down are in my opinion unnecessary disk accesses because of lack of cheap RAM. CPU doesn't usually slow it down that much.