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Subsentient writes:
"I'm a C programmer and Linux enthusiast. For some time, I've had it on my agenda to build the new version of my i586/Pentium 1 compatible distro, since I have a lot of machines that aren't i686 that are still pretty useful.
Let me tell you, since I started working on this, I've been in hell these last few days! The Pentium Pro was the first chip to support CMOV (Conditional move), and although that was many years ago, lots of chips were still manufactured that didn't support this (or had it broken), including many semi-modern VIA chips, and the old AMD K6.
Just about every package that has to deal with multimedia has lots of inline assembler, and most of it contains CMOV. Most packages let you disable it, either with a switch like ./configure --disable-asm or by tricking it into thinking your chip doesn't support it, but some of them (like MPlayer, libvpx/vp9) do NOT. This means, that although my machines are otherwise full blown, good, honest x86-32 chips, I cannot use that software at all, because it always builds in bad instructions, thanks to these huge amounts of inline assembly!
Of course, then there's the fact that these packages, that could otherwise possibly build and work on all types of chips, are now limited to what's usually the ARM/PPC/x86 triumvirate (sorry, no SPARC Linux!), and the small issue that inline assembly is not actually supported by the C standard.
Is assembly worth it for the handicaps and trouble that it brings? Personally I am a language lawyer/standard Nazi, so inline ASM doesn't sit well with me for additional reasons."
(Score: 4, Insightful) by Anonymous Coward on Saturday March 08 2014, @05:47AM
Seems worth it to me. If it only causes problems to the market segment that is:
a) still using old pentiums
AND
b) trying to run multimedia stuff.
AND
c) trying to use newer software to do it.
I've used 386, 486s, pentiums and the other CPUs around 15-20 years ago, and they weren't that great at doing multimedia stuff. I can't remember what percent CPU was required to do full screen video but it's likely to have been double digits for weaker CPUs, and back then full screen video was typically at best 640x480 (24-30fps was an achievement on slower pentiums), and more likely NTSC/PAL (352x240) or 320x240.
Which was probably why some of the new instructions you grumble about were added - so that slightly more powerful CPUs like the Pentium Pro could do things more efficiently. IIRC back then they even had stuff like hardware assistance for MPEG playback. It was even common for users back then to complain that programs like Winamp were using too much CPU (20+% on P133) and that's merely for a fancy MP3 player.
So even if you replaced all those pesky instructions with working code, you might only be able to do 352x240 video at 24fps on old Pentiums, and only if they were encoded with not so CPU intensive encodings. Here's a random USENET thread from the past: https://groups.google.com/forum/#!search/pentium$2 0133$20max$20fps$20movie/alt.comp.periphs.mainboar d.tyan/NUxgNVPI_EQ/F1BoFGtgmc0J [google.com]
Search for more relevant ones if you wish.
It'll definitely be a noteworthy achievement if you can playback video encoded with modern encodings fast enough on a Pentium- please submit that story if you manage it!
You seem a bit like someone with a collection of ancient cars finding that the newer car audio stuff doesn't fit in them without a lot of work. You should be enjoying the challenge actually. If you don't enjoy it then maybe you need to adjust the focus/direction of your hobby a bit.
(Score: 2) by hankwang on Saturday March 08 2014, @11:44AM
I wonder what one could possibly want to use a Pentium for, these days, other than running some kind of computer museum or running some ancient industrial ISA hardware that is difficult to replace. (Even then, one can buy industrial computers that combine modern CPUs with ISA buses.) A Raspberry Pi has much more computing power than that old Pentium, at 5-10% of the power consumption. (At Dutch electricity prices, the break-even is at about 3 months of continuous use - EUR 0.22/kWh, 75 versus 5 W.)
Avantslash: Slashdot+SoylentNews for mobile [avantslash.org].
(Score: 0) by Anonymous Coward on Saturday March 08 2014, @02:52PM
I'm wondering if an x86 emulator on a modern smartphone could run Linux, mplayer and be faster than one of his pentium machines... ;)
For some perspective Intel Core 2 came out in 2006. And the first Opterons and Athlon 64s in 2003.4 _3800+_(45W)_vs_Intel_Pentium_100_MHz_(A80502-100) .html [cpu-world.com]
Compare Athlon 64s vs Pentium 100MHz: http://www.cpu-world.com/Compare/255/AMD_Athlon_6
So even 10 year old machines are about 50-200x faster than Pentium 100MHz (about 20 years old).
If you replace the offending ASM instructions, how much of the current multimedia stuff out there will work in practice if the CPU is 100x slower? Good luck playing Full HD videos ;).
So yeah use pentium systems as a hobby if you wish, but complaining that mplayer doesn't work? What next complain mplayer can't play 1080p on your pentium?
(Score: 1) by epitaxial on Saturday March 08 2014, @12:24PM
I see more powerful computers sitting out for the trash and for sale in thrift stores. Throw away those Pentium 1 based boxes already. Hell you could replace them with $45 BeagleBone Black boards and recoup your electricity costs in the first year alone.