Re: ParallelMap in FindMinimum getting slower
- To: mathgroup at smc.vnet.net
- Subject: [mg122044] Re: ParallelMap in FindMinimum getting slower
- From: Oliver Ruebenkoenig <ruebenko at wolfram.com>
- Date: Mon, 10 Oct 2011 05:53:21 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <201110070848.EAA07424@smc.vnet.net> <Pine.LNX.4.63.1110070439250.26775@wopr.wolfram.com>
On Fri, 7 Oct 2011, Rafael Reiter wrote: > Hi, > > find the file attached. You can just hit "Evaluate Notebook". > I noticed in top that the used memory is also increasing all the time. I > guess the distributed data gets bigger and bigger, but what is it? > > Rafael I do not have the time to read you notebook in all detail. Here are some random ideas: - Use $HistoryLength = 0 (also evaluated via ParallelEvaluate) - Some of the data you pass around are not packed arrays: e.g. try Bloch[nkx_, nky_] := Developer`ToPackedArray[N[BlochH /. kx -> nkx /. ky -> nky]]; - Also the path data contains integer and reals. Perhaps that could be avoided. - After //Chop use //N//Developer`ToPackedArray - Perhaps replace the Module with Block Hope this contains the right clue. Oliver > > On 07.10.2011 11:39, Oliver Ruebenkoenig wrote: >> On Fri, 7 Oct 2011, Rafael Reiter wrote: >> >>> Hi everyone, >>> >>> I use ParallelMap with Mathematica on Linux to solve 100 eigenvalue >>> problems on 4 kernels. This operation ist repeated very often by >>> FindMinimum, and over the course of time the performance drops >>> significantly. Using top, you can see that the CPU used by the master >>> kernel increases, and the CPU used by the slave kernels decreases from >>> 70 to appr. 20 percent. Has anyone else experienced this phenomenon? >>> >>> Best wishes, >>> Rafael >>> >>> >> >> Can you send the example? >> >> Oliver > >
- References:
- ParallelMap in FindMinimum getting slower
- From: Rafael Reiter <mail@zonk.at>
- ParallelMap in FindMinimum getting slower