On Mon, Nov 16, 2009 at 8:32 AM, Elbers, Jan <span dir="ltr"><<a href="mailto:Jan.Elbers@wur.nl">Jan.Elbers@wur.nl</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
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<div><font face="Arial" size="2"><span>Dear Mr. Da
Silva,</span></font></div>
<div><font face="Arial" size="2"><span></span></font> </div></div></blockquote><div><br></div><div>Please send messages to the gradsusr list...</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
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<div><font face="Arial" size="2"><span>When defining large
arrays i seem to run into a memory limitation of Opengrads
2.0.a7.oga.3.</span></font></div>
<div><font face="Arial" size="2"><span>Could you please let
me know if there is a limit on one individial array or on all defined arrays
together?</span></font></div>
<div><font face="Arial" size="2"><span></span></font> </div>
<div><font face="Arial" size="2"><span>I am using ECWMF
re-analisis data for the northern hemispere resulting in arrays of 181 x 720 x
488 grid cells (X x Y x T). At the point where it goes wrong opengrads.exe has
allocated about 1 Gb of memory on my PC which has 2 Gb of
RAM.</span></font></div>
<div><font face="Arial" size="2"><span></span></font> </div></div></blockquote><div><br></div><div>One 3D array of this size consumes around 500Mb of memory as GrADS v2 uses double precision (8 bytes) to store each gridcell. Depending on your format, it could be caching some of the I/O, which results in even more memory usage. Your may stretching the limits of your hardware.</div>
<div><br></div><div>Now, GrADS v1.x uses 4 bytes to store each grid cell resulting in about half the memory usage of GrADS v2. Unless you need GrADS v2 specific features, the Win32 Superpack v1.9-rc1 is probably the best option for dealing with such large arrays on your hardware:</div>
<div><br></div><div> <a href="https://sourceforge.net/projects/opengrads/files/grads1-windows/1.9.0-2/">https://sourceforge.net/projects/opengrads/files/grads1-windows/1.9.0-2/</a></div><div><br></div><div>(I just realized that we never released v1.10.r2.oga for Windows...)</div>
<div><br></div><div> Arlindo</div><div><br></div><div><br></div><div> </div></div>-- <br>Arlindo da Silva<br><a href="mailto:dasilva@alum.mit.edu">dasilva@alum.mit.edu</a><br>