Hello Ruben! On Mon, Sep 24, 2012 at 8:11 AM, Ruben Van Boxem <[email protected]> wrote: > Hi everyone, > > I started investigating my gdb build's slowness. > ... > When I do > gdb testapp > set verbose on > run > > I see that the extra time is spent in the "Loading Symbols from" > QtCore4d.dll (2 vs 6 seconds) and QtGui4d.dll (6 vs 18 seconds). This is my > visual perception only.
Thanks for the suggestion of running "set verbose on". Here's my data point for a very simple gui app that displays a sqlite table: QtCored4.dll: 0:19 (time "Reading symbols from") QtGuid4.dll: 1:28 (time "Reading symbols from") other: 0:01 (maybe mostly QtSqld4.dll / qsqlited4.dll) total: 1:48 (total time from "run" to displaying the app) (Times are given as minutes:seconds, and are good to probably about a second.) So I see what Ruben sees (most of the time spent reading the symbols from the two big Qt dll's), except that the times I see are much longer -- three to four times as long. I am running on a two-core, 1.60 GHz, 64-bit windows 7 system. Task manager suggests that gdb is more or less saturating one of the cores. (So processor speed probably explains part of my difference with Ruben, but not all.) This is with: g++ (GCC) 4.7.0 20110829 (experimental) GNU gdb (GDB) 7.3.0.20110829-cvs from Ruben's build: x86_64-w64-mingw32-gcc-4.7.0-stdthread_rubenvb.7z Qt is 4.8.0-rc1, and both Qt and the test app were plain-vanilla builds using the above compiler. > I have now rebuilt gdb with "--disable-nls" and I believe this is the thing. > Don't ask me why this is. The startup time reduces from ~19 seconds to 6-7 > seconds, which is the same as mingw-builds gdb. I don't really understand what compatibility requirements there are between g++ and gdb, but if you think that I could use your new gdb with my existing Qt / test app, I'd be happy to give it a try and report back timings. (I don't really want to rebuild Qt in order to perform the test.) > ... > Another mystery solved by your anonymous hero, Indeed. Truly an International Man of Mystery! > Ruben Thanks for looking into this. K. Frank ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Mingw-w64-public mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mingw-w64-public
