Re: specs for a netbsd build system?

[Mayuresh Kathe <mayuresh%kathe.in@localhost>]

On Sun, Jun 22, 2014 at 08:34:10AM -0400, Greg Troxel wrote:
> 
> Mayuresh Kathe <mayuresh%kathe.in@localhost> writes:
> 
> > i have no idea about what kind of hardware would be required for
> > performing an entire netbsd build within acceptable time-frames,
> > say 1 hour (without x win).
> >
> > may i please get advice on rough specifications for the same?
> > stuff like;
> > 1. preferable processor (intel! amd!),
> > 2. processing power (clock rate, number of cores, cache, etc),
> > 3. memory (size and type),
> > 4. hard disk (space and type),
> >
> > i have a budget of around us$600.
> 
> Building all of NetBSD (with build.sh) takes some amount of time when
> starting from scratch.  Doing an update build (-u) means that most
> things don't get rebuilt if nothing has changed, and is much faster.
> 
> At this point, given that you want something PCish, you definitely want
> to get something that can run in amd64 mode, so it can have more memory.
> 
> I think as long as you have 50G of disk to devote to src/obj and 4G of
> RAM, and a processor from the last 5 years, you'll be fine, assuming you
> are just building only a few branch/arches.   I can't see you wanting
> more than 200G for NetBSD itself.  (pkgsrc bulk builds are piggier;
> there are ~1E4 packages.)
> 
> As a concrete datapoint, I have a system (probably 1.5 years old):
> 
>   cpu0 at mainbus0 apid 0: Intel(R) Core(TM) i5-2310 CPU @ 2.90GHz, id 0x206a7
>   cpu1 at mainbus0 apid 2: Intel(R) Core(TM) i5-2310 CPU @ 2.90GHz, id 0x206a7
>   cpu2 at mainbus0 apid 4: Intel(R) Core(TM) i5-2310 CPU @ 2.90GHz, id 0x206a7
>   cpu3 at mainbus0 apid 6: Intel(R) Core(TM) i5-2310 CPU @ 2.90GHz, id 0x206a7
>   [hyperthreading disabled; note the even APID values]
>   total memory = 3569 MB
>   avail memory = 3497 MB
> 
>   running NetBSD/i386 for historical reasons, even though the box has
>   16G of RAM.  That's a clue that using only 3.5 of 16G has not annoyed
>   me enough to switch.  But you should definitely start out in amd64 mode.
> 
>   128G SSD for root/usr
>   1T regular disk for other stuff
> 
> This computer cost about $1100, with a nice case and power supply,
> already built/tested (it's at work), but I don't really remember - it
> might have been only $900.  It's far more than you need, though.
> 
> It does a full release build (all the way to ISO), including X, with -u
> (and a previous build done) of the i386 sources in about 24 minutes.  My
> belief is that even if the very first time takes 8 hours, that's ok,
> because you'll be doing -u most of the time.  I think it takes one to a
> few hours to do the first build, but I don't really know/remember
> because it happens so rarely.  I just start a script to build several
> arches and check it the next day.
> 
> I have source trees for 4/5/6/current, and obj/tooldir/destdir/releasedir
> for multiple architectures, a total of 16 combinations.  This is all
> fitting in a 1T disk without really noticing it.  My /usr/obj (which has
> releasedir/destdir/tooldir in it also) for NetBSD-current and 7
> architectures is 58G.  You definitely want to leave those and use -u.
> 
> We also have a box with 12 real CPUs and 12G of RAM:
> 
>   cpu11 at mainbus0 apid 52: Intel(R) Xeon(R) CPU           X5675  @ 3.07GHz, 
> id 0x206c2
> 
> and some SSD and some hardware raid scsi.  It's definitely a lot faster
> - I think it can do a full build with no objdir in 25 minutes -- but
> it's way too expensive for your price point, rackmount, power-hungry,
> etc.  and also totally unnecessary.
> 
> A further datapoint is that I have also used a machine with 1 CPU (with
> hyperthreading) and 2G of RAM:
> 
>   cpu0 at mainbus0 apid 0: Intel 686-class, 3400MHz, id 0xf43
> 
> This was new in 2006.   It would probably be a little too slow for you,
> but I bet it would do.  I built netbsd on it until a few years ago, and
> stopped because I wanted to maintain fewer source trees with my
> private tweaks, more than I wanted to avoid building on it.
> 
> 
> Given that you said $600, I would try to get a 1T disk, 8G of RAM, and a
> 4-core processor, backing away from the very top speeds that seem to
> cost way extra, and put it together yourself.  I haven't priced things
> lately, so I don't know if that fits.  The increase in speed lately has
> been slowing, but newer motherboards do have faster memory that the
> older ones, and caches are often bigger.  But you may be able to get
> some gamer friend's 3 year old system which is probably just fine.
> 
> 
> The big question is getting a motherboard where the builtin graphics
> works well with X, if you want to run that.

thanks for the fantastic advice, your detailed mail is really helpful.

i will not be going with x-win, i dislike it to the point of once
leading a team which built a graphical operating environment running
atop the linux graphics framebuffer (directly).
we called it the "nevyos" effort. :)

thanks again,

~mayuresh