Hi Ben, On 11/13/2012 09:53 AM, Kirk, Benjamin (JSC-EG311) wrote: > Thanks for the info. Is this something that I could test, or could you send > me a patch for one of the examples to crank them up to a big problem size?
I'll send you a patch for one of the examples to make a large RB IO file like the one I mentioned. > Also, what type of computer / filesystem are you testing this on? Straight > local disk or what? This was on my laptop with Ubuntu 12.04, straight local disk... > 301MB/19 = 15.8 MB/sec, so I expect there is still some room for improvement. > > But there is a lot of overhead too - indexing dof objects, assigning values, > copies so as not to overload processor 0, etc.. > > I'll benchmark the raw underlying XDR I/O performance - how quickly Xdr can > write say 500MB - so we know how much higher that number could reasonably go. OK, that'll be interesting. David On Nov 12, 2012, at 8:32 PM, David Knezevic <dkneze...@seas.harvard.edu> wrote: >> On 11/12/2012 09:23 PM, David Knezevic wrote: >>> On 11/06/2012 05:24 PM, Kirk, Benjamin (JSC-EG311) wrote: >>>> Dave, my ultimate fix for you will be extending this to write >>>> >>>> for node… >>>> for vec… >>>> for var… >>>> for comp… >>>> >>>> or some permutation thereof, which will necessitate writing all the >>>> reduced basis vectors to a single file, in order to get maximum >>>> performance. I assume that's OK with you? >>>> >>> Hi Ben, >>> >>> I've tried out the new RB IO on a problem with a "merged" .xdr file that >>> is 301MB --- previously I read this data in as many separate .xdr files >>> each of size 130kB. >>> >>> In serial, it took about 22 seconds to do the read in the merged case >>> (i.e. RBEvaluation::read_in_vectors() took 22 seconds) vs. about 42 >>> seconds in the "separated" case. >>> >>> So it gives a 2x speedup, which is very helpful indeed. Though I recall >>> that a 30x speedup didn't seem out of the question --- are there >>> possibly some parameters (block sizes, etc, like before?) that I can try >>> tweaking to see if we can speed up the merged case further? >> P.S. It occurred to me that it's worth benchmarking >> RBEvaluation::read_in_vectors in a bit more detail, and 19 of the 22 >> seconds is spent in System::read_serialized_vectors(). (The last 3 >> seconds in mostly due to the vector allocation.) >> >> David >> ------------------------------------------------------------------------------ Monitor your physical, virtual and cloud infrastructure from a single web console. Get in-depth insight into apps, servers, databases, vmware, SAP, cloud infrastructure, etc. Download 30-day Free Trial. Pricing starts from $795 for 25 servers or applications! http://p.sf.net/sfu/zoho_dev2dev_nov _______________________________________________ Libmesh-devel mailing list Libmesh-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmesh-devel
