Le mardi 26 janvier 2016 à 12:59 -0800, jda a écrit : > The OSes and the Julia versions are all 64-bit. Thanks for the .exe > links, I was looking for them. Good suggestion to install the 0.4.3 > version of Julia on the mac laptop. > > What I found has led me to a different question. I have found that > actually the same size matrix that before ran just fine on the mac > laptop no longer run -- giving the OutOfMemory error now. So this > problem seems to *not* be related to the version of Julia but rather > the state of the system. I must say in advance that I am trying to > push the limits -- trying to run simulations for the biggest grid > possible for the best results. In doing so it seems that I need to > learn much more about optimizing memory usage and possible (?) other > aspects of how the system is setup? Any info that would help me to > navigate this would be greatly appreciated. It's hard to tell without seeing the code, but in general you should avoid allocating temporary arrays by unrolling your loops and using in- place versions of functions where possible. Of course, also make sure that there is no type instability in your code which would trigger unwanted memory allocations.
You could also use Float32 instead of Float64 if reduced precision isn't an issue for your application. Regards > > On Tuesday, January 26, 2016 at 4:53:38 AM UTC-5, Milan Bouchet-Valat > wrote: > > Le lundi 25 janvier 2016 à 21:51 -0800, jda a écrit : > > > I've run into the following problem while running a simulation > > code > > > (of a differential equation). Because of the nature of the > > > problem, the matrices are dense. In particular one line of code > > that > > > runs the backslash operator gives an OutOfMemory error on one > > > computer but not on another computer. > > > > > > > > > The error is: > > > ERROR: LoadError: OutOfMemoryError() > > > in .* at arraymath.jl:118 > > > in * at abstractarraymath.jl:54 > > > in functionName at C:\Users\user\Google Drive\codefile.jl:158 > > > in include at boot.jl:261 > > > in include_from_node1 at loading.jl:304 > > > while loading C:\Users\user\Google Drive\codefile.jl, in > > expression > > > starting > > > on line 155 > > > > > > (error points to backslash operator ) > > > > > > > > > Info for the computer that works fine: > > > mac laptop > > > 1.6 GHz i5 processor > > > 4 GB memory > > > 250 GB > > > running Julia 0.4.1 > > > > > > Info for the computer that gives the error: > > > windows desktop > > > Intel(R) Core(TM) i5-4590 CPU @3.30GHz > > > 8 GB memory > > > 420 GB drive > > > running Julia 0.4.3 > > An important information is whether these are 64-bit OSes, and > > whether > > you're using the 32-bit or 64-bit Julia. The latter will use more > > memory to store pointers and integers. > > > > > Both computers are not running any other programs, and are both > > > fairly new with plenty of space available (the computers > > > are specifically designated to run such code). I am sure that > > my > > > next step should be to install Julia 0.4.1 on the windows > > computer to > > > see if that helps, but it may take me some time to sort through > > the > > > instructions for installing old versions of Julia. > > Should be very easy to do: > > https://s3.amazonaws.com/julialang/bin/winnt/x86/0.4/julia-0.4.1-wi > > n32.exe > > https://s3.amazonaws.com/julialang/bin/winnt/x64/0.4/julia-0.4.1-wi > > n64.exe > > > > You can also install 0.4.3 on the Mac machine and see whether it > > still > > works. > > > > > I wondered whether anyone would have some insight as to why/how > > this > > > error could occur on a newer version of Julia and on a better > > > machine? > > AFAIK there shouldn't be any large difference, but who knows? > > > > > > Regards
