<div dir="ltr"><div class="gmail_default" style="font-size:small">Walter,</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">Thanks for sending a little script that shows the issue. I'm not seeing the same large difference of results as you, but I do see some slight increase. If I run the script multiple times, I get very different results, so I'm not sure exactly what kind of memory usage is being reported by the "ps" command you provided.</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">What version of NCL are you using?</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">--Mary</div><div class="gmail_default" style="font-size:small"><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Oct 28, 2015 at 11:22 AM, Walter Hannah <span dir="ltr"><<a href="mailto:walter@hannahlab.org" target="_blank">walter@hannahlab.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">I'm having lots of "malloc" errors lately, and I realized that when I use the "delete" function, NCL doesn't free up as much memory as it created!!!<div><br></div><div>After doing some sleuthing I figured out that the problem happens after I use the reassingment operator ":=" to reduce a variable to a subset of itself like this:</div><div><br></div><div><blockquote style="margin:0px 0px 0px 40px;border:none;padding:0px"><font face="monospace, monospace">X := X(0,:)</font></blockquote></div><div><br></div><div>I've come up with a stand alone NCL script (see below) that anyone should be able to run on a linux machine to reproduce the problem. It prints out the memory usage from the "ps" command. </div><div><br></div><div><blockquote style="margin:0px 0px 0px 40px;border:none;padding:0px"><div><font face="monospace, monospace">procedure printMem (msg)</font></div><div><div><font face="monospace, monospace">local rss,cmd</font></div><div><font face="monospace, monospace">begin</font></div><div><font face="monospace, monospace"> cmd = "ps --no-headers -o 'rss' -C ncl"</font></div><div><font face="monospace, monospace"> rss = max(toint(systemfunc(cmd))) / 1024.</font></div></div><div><font face="monospace, monospace"> print("NCL memory: "+sprintf("%6.2f",rss)+" "+msg)</font></div><div><font face="monospace, monospace">end</font></div><div><font face="monospace, monospace"><br></font></div><div><font face="monospace, monospace">begin</font></div><div><font face="monospace, monospace"> dims = (/10000,100,100/)</font></div><div><font face="monospace, monospace"><br></font></div><div><font face="monospace, monospace"> print("")</font></div><div><font face="monospace, monospace"> printMem("basline memory")</font></div><div><font face="monospace, monospace"> print("")</font></div><div><font face="monospace, monospace"> ;-----------------------------------------------------</font></div><div><font face="monospace, monospace"> ;-----------------------------------------------------</font></div><div><font face="monospace, monospace"> X = new( dims ,float)</font></div><div><font face="monospace, monospace"> printMem("X created")</font></div><div><font face="monospace, monospace"> delete(X)</font></div><div><font face="monospace, monospace"> printMem("X deleted")</font></div><div><font face="monospace, monospace"> print("")</font></div><div><font face="monospace, monospace"> ;-----------------------------------------------------</font></div><div><font face="monospace, monospace"> ;-----------------------------------------------------</font></div><div><font face="monospace, monospace"> X = new( dims ,float)</font></div><div><font face="monospace, monospace"> printMem("X created")</font></div><div><font face="monospace, monospace"> X := X</font></div><div><font face="monospace, monospace"> printMem("X reassigned")</font></div><div><font face="monospace, monospace"> delete(X)</font></div><div><font face="monospace, monospace"> printMem("X deleted")</font></div><div><font face="monospace, monospace"> print("")</font></div><div><font face="monospace, monospace"> ;-----------------------------------------------------</font></div><div><font face="monospace, monospace"> ;-----------------------------------------------------</font></div><div><font face="monospace, monospace">end </font></div></blockquote></div><div><br></div><div>The output of the script on my linux machine is:</div><div><br></div><div><blockquote style="margin:0px 0px 0px 40px;border:none;padding:0px"><div><font face="monospace, monospace">(0)</font></div><div><font face="monospace, monospace">(0)<span style="white-space:pre-wrap"> </span>NCL memory: 74.38 basline memory</font></div><div><font face="monospace, monospace">(0)</font></div><div><font face="monospace, monospace">(0)<span style="white-space:pre-wrap"> </span>NCL memory: 456.11 X created</font></div><div><font face="monospace, monospace">(0)<span style="white-space:pre-wrap"> </span>NCL memory: 74.66 X deleted</font></div><div><font face="monospace, monospace">(0)</font></div><div><font face="monospace, monospace">(0)<span style="white-space:pre-wrap"> </span>NCL memory: 456.13 X created</font></div><div><font face="monospace, monospace">(0)<span style="white-space:pre-wrap"> </span>NCL memory: 837.44 X reassigned</font></div><div><font face="monospace, monospace">(0)<span style="white-space:pre-wrap"> </span>NCL memory: 456.14 X deleted</font></div><div><font face="monospace, monospace">(0)</font></div></blockquote></div><div><br></div><div>So, after using doing the reassignment it seems that a copy of the variable is left in memory and never cleared.</div><div><br></div><div>I can work around it for now, but I wanted to ask if anyone knew about this, and also can it be fixed?</div><div><br></div><div>Thanks,</div><div>Walter Hannah</div></div>
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