There's a reasonable chance that Debian/Ubuntu has a pessimized OpenBLAS for the sake of portability.
On Sat, Aug 23, 2014 at 3:18 AM, Don MacMillen <[email protected]> wrote: > sudo apt-get install libopenblas-dev > > julia> @time begin a = rand(5000,5000); b = rand(5000); x =a\b end; > elapsed time: 2.517259033 seconds (400100776 bytes allocated, 1.44% gc > time) > > Thanks John. > > On Friday, August 22, 2014 11:11:09 PM UTC-7, John Myles White wrote: > >> Perhaps you have a defective BLAS installation for 0.3? >> >> — John >> >> >> On Aug 22, 2014, at 11:08 PM, Don MacMillen <[email protected]> wrote: >> >> Hmmm, thx for the experiment. To clarify, I assumed that the normal >> behavior would have been closer >> to the 4.0 time, but I don't have anything earlier. The 0.3 was just >> updated using apt-get on Ubuntu 14.04 >> (VM running on windows). 0.4 was of course cloned and compiled. Just >> scraped and re-installed 0.3 >> with apt-get, and I still see the same behavior. (This time remembering >> to discard initial compile time) >> >> julia> @time begin a = rand(5000,5000); b = rand(5000); x =a\b end; >> elapsed time: 30.509950844 seconds (400100776 bytes allocated, 0.11% gc >> time) >> >> It's mystery to me. If I learn anything more, will let you know. >> Thanks again. >> >> Don >> >> >> >> On Friday, August 22, 2014 9:54:22 PM UTC-7, John Myles White wrote: >>> >>> I don’t see this behavior at all on my system. >>> >>> After discarding an intial compilation step, here’s what I get: >>> >>> 0.3 — elapsed time: 3.013803287 seconds (400120776 bytes allocated, >>> 1.77% gc time) >>> 0.4 — elapsed time: 2.920384195 seconds (400120776 bytes allocated, >>> 1.89% gc time) >>> >>> Also to clarify: do you mean to refer to 0.3 as a regression relative >>> 0.4? >>> >>> — John >>> >>> On Aug 22, 2014, at 9:50 PM, Don MacMillen <[email protected]> wrote: >>> >>> > Is anyone else seeing the following? If not, what could I have done >>> to my env to trigger it? >>> > >>> > Thx. >>> > >>> > julia> VERSION >>> > v"0.3.0" >>> > >>> > julia> @time begin a = rand(5000,5000); b = rand(5000); x =a\b end; >>> > elapsed time: 31.413347385 seconds (440084348 bytes allocated, 0.12% >>> gc time) >>> > >>> > julia> >>> > >>> > ---------------- >>> > >>> > julia> VERSION >>> > v"0.4.0-dev+308" >>> > >>> > julia> @time begin a = rand(5000,5000); b = rand(5000); x =a\b end; >>> > elapsed time: 1.686715561 seconds (431769824 bytes allocated, 0.87% gc >>> time) >>> > >>> > julia> >>> > >>> >>> >>
