Date: Sun, 28 Sep 2003 16:14:18 -0500 From: "Charles Howse" <chowse@charter.net> To: "'Kent Stewart'" <kstewart@owt.com>, <freebsd-questions@freebsd.org> Subject: RE: Comparing buildworld times on twin machines Message-ID: <001c01c38605$7ae71970$04fea8c0@moe> In-Reply-To: <200309281354.45244.kstewart@owt.com>
next in thread | previous in thread | raw e-mail | index | archive | help
> On Sunday 28 September 2003 01:28 pm, Charles Howse wrote: > > > On Sunday 28 September 2003 12:37 pm, Charles Howse wrote: > > > > Hi, > > > > I have 2 machines on my home network with (almost) identical > > > > hardware. They both have Celeron 300, same motherboards, same > > > > BIOS, same options set in BIOS, etc. > > > > Same make.conf, same kernel config. > > > > I kill SETI@home before starting on each machine. > > > > The only difference is that curly has 128 MB ram where > > > > > > larry has only > > > > > > > 64. > > > > > > > > They *do not*, however have identical hard drives, even though > > > > each machine has 2 drives, with /usr/obj on the second drive of > > > > each machine. > > > > > > > > When I buildworld, I use the following command, and write the > > > > output to '$blog'. > > > > > > > > [portion of script omitted, entire script is attached as > > > > update1.sh] > > > > > > > > \time -aho $$blog make buildworld > > > > > > > > [snip] > > > > > > > > Larry can buildworld in 1 hr 57 mins. > > > > It takes curly 3 hrs 16 mins, even though curly has twice the > > > > ram. > > > > > > > > If I watch the compile, with one eye on the disk activity light, > > > > it seems to me that the process is largely CPU intensive, > > > > therefore I would expect that the buildworld times should be > > > > roughly equal. > > > > > > > > 1) How can I determine what might be causing curly to take so > > > > long compared to larry? > > > > > > > > 2) Since curly runs httpd, and vsftpd, is it acceptable to run > > > > the entire build/install process in single-user mode in order to > > > > prevent other processes from eating CPU cycles? > > > > > > On my systems, which all run setiathome, I only see a few percent > > > variation in buildworld time with seti running. I start > > > setiathome with > > > a -nice 19 so that it doesn't interfere. > > > > Me, too. > > > > > You might be able to see some of the processes running using top. > > > You could always stop apache. > > > > True, I could do that, but what is your opinion on running=20 > the entire > > build/install process from single-user mode? (my original question) >=20 > That would work but I run my buildworlds from a consol in KDE and I=20 > don't see that much difference and running it with KDE=20 > stopped. Running=20 > it single user mode may be faster than shutting apache down. But then=20 > you won't know what caused it to begin with.=20 >=20 > I have scripts in /root/bin to start and stop it and start=20 > it. They are >=20 > # cat startapache > #! /bin/sh > /usr/local/sbin/apachectl start >=20 > # cat stopapache > #! /bin/sh > /usr/local/sbin/apachectl stop >=20 > > > > > I kind of wonder if you have cache turned on in the cpu. That much > > > difference is pretty hard to come up with unless your 2=20 > daemons are > > > interfering. You might see that running top. Watch the swap to see > > > if anything is happening. > > > > Oh, geeeez, technical stuff! ;-) I'm a real dumbass in=20 > the BIOS. I > > just select "Load High Performance Settings" on each machine, and > > then change the boot order to my liking. > > I did notice that 'internal cache' is set to 'write-back'. > > Am I on the right track? >=20 > I think that performance would turn things on. You may have a=20 > bad cache=20 > but that isn't what I would look at first. Not all Celerons have the=20 > same kind of cache. I gave a Celeron 433a, which had the on board=20 > cache, to some friends that needed a computer. I had swapped=20 > it out and=20 > all the needed to do was buy a montior. >=20 > Using PC-100 memory is about 15% faster than PC-66 memory.=20 > This was the=20 > difference in accumulated wu processing time for seti on 2xx wus with=20 > the different speed memory. Jumping up to PC-133 didn't change=20 > anything. That is like getting a cpu upgrade for just a few=20 > $s. A 128MB=20 > pc-100 sdimm runs around $35 at Best Buy and you know you can=20 > do better=20 > than that off of the Internet. >=20 > > *Exactly* how do I watch the swap...in top? > > >=20 > Watch top and see if something is forcing processes to swap=20 > by watching=20 > the swap line of information.=20 >=20 > You can also see if apache is accruing time while you do the=20 > build. It=20 > shows you the processes as they accrue time and which one is=20 > getting a=20 > lot of time is what you are looking for. You can't do this in single=20 > user mode because you only have the console. Very good, thanks for your input!
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?001c01c38605$7ae71970$04fea8c0>