On 01/03/2014 04:03 PM, Mark Lee wrote:

On Fri, 2014-01-03 at 15:55 -0500, Isaac Dupree wrote:

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On 01/03/2014 10:37 AM, Anatol Pomozov wrote:

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Using -j$(cpunum) is a sane default that saves a lot of time to users.

I agree, but for the record, 'nice' and scheduling are no panacea in my experience. It's fine for CPU loads, but compilations are also disk-heavy (which mattered when I used a spinning disk) and sometimes RAM-heavy (-j8 on my pet C++ project uses 2GB of RAM, which could push other programs I'm using into swap).

-Isaac

Salutations,

I got to ask why you are running make with 8 threads on a system with only 2 GB of ram?

Heh. Well, I have 8 GB of RAM, but I'm often using most of it already. $(nproc) is 8 because there are 4 cores with each with hyperthreading (Intel Core i7). The project builds roughly at the same speed on this box at anywhere from -j4 to -j8; if that generalizes to other projects and there's an easy way to count cores not hyperthreads, cores might be a better Arch default. Shrugs. There are quite a few 4GB i7 systems out there too. Quad core ARM systems are another point on the cores-to-RAM-ratio spectrum. Probably most code doesn't consume 256 MB RAM per GCC invocation. C++'s templates and lack of module system... -Isaac