On 17/03/2014 10:36, Marco van de Voort wrote: > In our previous episode, Reinier Olislagers said: >>> No. Even not on Windows. You need the number of physical cores, not logical >>> ones. This will return the duplicate number of cores on systems with >>> hyperthreading. (I tested on my system and indeed, 8 instead of 4) >> >> Do you see a performance dropoff or instability/crashes... or both when >> increasing the job number past the amount of physical cores? > > IIRC yes, 5 is still increasing, 6 is lower than 4 or 5. If I boot it up in > windows, I'll retest. Ok, thanks.
> The point was more that the autodetection is IMHO still too immature to > enable by default. Got it. It's disabled for now on Windows anyway as fpcup uses make 3.80 by default to support the 2.6.x series (see Florian's post). > But those are SSD based values. Increased disk seeking might make it worse > on HDDs. Ok. Quick test on Linux x64 VM seems to show increasing to 8 (matching my # of physical cores, no hyperthreading on my CPU) does increase performance... using the famous unit of time called "number of cups of coffee I thought I drank while waiting for the compile" _______________________________________________ fpc-devel maillist - [email protected] http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-devel
