On 01-08-11 18:47, Krzysztof Kosiński wrote:
2011/8/1 Jasper van de Gronde <th.v.d.gronde@...528...>:
Currently I'm only working on a notebook (three years old, and lets just say I bought it for the daylight readable screen and light weight, not its performance) and frankly this is starting to be a nuisance. Usually a complete build takes about six hours or so, but recently it took as much as ten hours... (Probably because part of the time I was also doing something on the side, but still.) As a stop gap measure I've now started using ccache, but obviously that doesn't help much when doing normal builds.
Ten hours is ridiculously long even when using btool. I get far lower times (1.5h max) in virtualized Windows XP. I think the build process might be RAM starved. You need at least 1.2GB of free RAM to keep all files in the page cache.
1.2GB!!! In any case, since my machine has 2GB, that's indeed not an unlikely contributor to lengthy build times.
(BTW, the ten hours was exceptional even for me, half that is more typical.)
So I'm beginning to consider buying a new machine and am wondering what sort of improvement I can expect from what kind of machine (using a complete clean build as a kind of benchmark).
Go for a multicore machine with at least 4GB of RAM. I have Intel Core i7-920, from the low end of the i7 family, 6GB RAM and a standard HDD, and a clean build with make -j8 takes only a few minutes. Most of the time on small rebuilds (e.g. a few files changed) is actually spent processing the Autotools cruft in makefiles, and linking is a close second.
I'm now trying to find a quad core laptop (a desktop machine isn't really an option for me at the moment) that isn't too heavy, apparently a tricky combination, so I'll probably have to compromise somewhere.