On Thu, Nov 10, 2011 at 11:00 PM, Jeffrey Horner <jeffrey.hor...@gmail.com> wrote: > On Thu, Nov 10, 2011 at 10:54 PM, Jeffrey Horner > <jeffrey.hor...@gmail.com> wrote: >> Hi, >> >> I've been tracking down a memory leak in an rApache application, >> http://data.vanderbilt.edu/rapache/bbplot. The code was deployed in >> 2007 and has survived numerous upgrades of both R and rApache >> (including upgrades and bugs in RMySQL). It's written in such a way so >> that web crawlers will download every possible URL the app will >> create. It's not a high-traffic app, but just about every line of code >> is executed at some point during a crawl by Google, Bing, etc. >> >> Here's the salient point: the app (well, just about all rApache apps) >> sets option warn to 0 to collect all warnings until a request is >> completed. It turns out that some requests will collect more than 50 >> warnings, and the result is an apache process that leaks memory until >> finally seg faulting somewhere in one of R's extra packages, if I >> recall correctly. >> >> After what seems like a month working on this problem, I think I've >> narrowed it down to a simple test case. I'm testing with R-devel >> r57624 on ubuntu linux. Running the following under valgrind: >> >> R -d valgrind >>> options(warn=0) >>> for (i in 1:51) factor(1,levels=c(1,1) # duplicate level warningcall > > Missed a closing parenthesis. should be : > >> options(warn=0) >> for (i in 1:51) factor(1,levels=c(1,1)) # duplicate level warningcall > >> >> and you should see "Invalid read" messages. I've narrowed it down to >> vwarningcall_dflt starting a new R context via begincontext() but >> returning early without calling endcontext() in errors.c: >> >> svn diff src/main/errors.c >> Index: src/main/errors.c >> =================================================================== >> --- src/main/errors.c (revision 57624) >> +++ src/main/errors.c (working copy) >> @@ -333,8 +333,11 @@ >> char *tr; int nc; >> if(!R_CollectWarnings) >> setupwarnings(); >> - if( R_CollectWarnings > 49 ) >> + if( R_CollectWarnings > 49 ) { >> + endcontext(&cntxt); >> + inWarning = 0; >> return; >> + } >> SET_VECTOR_ELT(R_Warnings, R_CollectWarnings, call); >> Rvsnprintf(buf, min(BUFSIZE, R_WarnLength+1), format, ap); >> if(R_WarnLength < BUFSIZE - 20 && strlen(buf) == R_WarnLength) >> >> This fix eliminates the "Invalid read" errors, but I'm unsure if it >> fixes my application. I'll find out tomorrow.
The memory leak was occurring in the Cairo package and it is fixed now, but the issue I spelled out above is still a concern. Jeff ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
