Re: What causes memory leaks during graceful restarts?
DM == Doug MacEachern [EMAIL PROTECTED] writes: DM what version of perl? what modperl Makefile.PL options? DM if you're using modperl as a dso, you'll need at least perl 5.6.1 and DM modperl-1.26 to prevent this leakage on restarts. Even with these versions, I get massive leakage on restart with FreeBSD. I always do a stop/start now. -- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Vivek Khera, Ph.D.Khera Communications, Inc. Internet: [EMAIL PROTECTED] Rockville, MD +1-240-453-8497 AIM: vivekkhera Y!: vivek_khera http://www.khera.org/~vivek/
Re: What causes memory leaks during graceful restarts?
At 6:56 PM -0700 5/21/02, Doug MacEachern wrote: On Tue, 21 May 2002, Dan Wilga wrote: I am using Perl 5.6.1, modperl 1.25, and yes it's a DSO. It's compiled with: with 1.25, you can also set the PERL_DESTRUCT_LEVEL environment variable to 2, either before starting the server: export PERL_DESTRUCT_LEVEL=2 apachectl start or using PerlSetEnv in httpd.conf the fix in modperl-1.26 is simply to use that value by default. Interesting. When I do that, I get the same problem I did when I tried to run with 1.25_01 and 1.26: Apache core dumps. I think I'll have to try compiling it again with the latest version of mod_perl, and perhaps not as a DSO. Dan Wilga [EMAIL PROTECTED] Web Technology Specialist http://www.mtholyoke.edu Mount Holyoke CollegeTel: 413-538-3027 South Hadley, MA 01075Seduced by the chocolate side of the Force
Re: What causes memory leaks during graceful restarts?
On Wed, 22 May 2002, Dan Wilga wrote: Interesting. When I do that, I get the same problem I did when I tried to run with 1.25_01 and 1.26: Apache core dumps. I think I'll have to try compiling it again with the latest version of mod_perl, and perhaps not as a DSO. possible that your are hitting the XSLoader vs. DynaLoader problem, where the list of dlhandles can be wiped out. try adding 'use DynaLoader ();' to your startup.pl before any other module is loaded.
Re: What causes memory leaks during graceful restarts?
At 8:41 AM -0700 5/22/02, Doug MacEachern wrote: On Wed, 22 May 2002, Dan Wilga wrote: Interesting. When I do that, I get the same problem I did when I tried to run with 1.25_01 and 1.26: Apache core dumps. I think I'll have to try compiling it again with the latest version of mod_perl, and perhaps not as a DSO. possible that your are hitting the XSLoader vs. DynaLoader problem, where the list of dlhandles can be wiped out. try adding 'use DynaLoader ();' to your startup.pl before any other module is loaded. Oh ho! That's it. Now when I gracefully restart, the memory loss is only about 29 Kb -- a very reasonable number. So if that's the reason for the core dump, is there a bug fix to the offending module in the works? Dan Wilga [EMAIL PROTECTED] Web Technology Specialist http://www.mtholyoke.edu Mount Holyoke CollegeTel: 413-538-3027 South Hadley, MA 01075Got Perl?
Re: What causes memory leaks during graceful restarts?
On Wed, 22 May 2002, Dan Wilga wrote:
Oh ho! That's it. Now when I gracefully restart, the memory loss is
only about 29 Kb -- a very reasonable number.
much better. with the modperl test suite, i only see a wee bit of leakage
on the first restart, then no leakage on restarts after that.
So if that's the reason for the core dump, is there a bug fix to the
offending module in the works?
it is fixed in 5.8.0-tobe with the patch below, which can also be applied
to 5.6.1
Index: ext/DynaLoader/DynaLoader_pm.PL
===
RCS file:
/usr/local/cvs_repository/perl-current-mirror/ext/DynaLoader/DynaLoader_pm.PL,v
retrieving revision 1.1.1.1
diff -u -r1.1.1.1 DynaLoader_pm.PL
--- ext/DynaLoader/DynaLoader_pm.PL 2001/01/04 01:55:35 1.1.1.1
+++ ext/DynaLoader/DynaLoader_pm.PL 2001/06/19 05:10:22
-80,8 +80,10
dl_require_symbols = (); # names of symbols we need
dl_resolve_using = (); # names of files to link with
dl_library_path= (); # path to look for files
-@dl_librefs = (); # things we have loaded
-@dl_modules = (); # Modules we have loaded
+
+#XSLoader.pm may have added elements before we were required
+#@dl_librefs = (); # things we have loaded
+#@dl_modules = (); # Modules we have loaded
# This is a fix to support DLD's unfortunate desire to relink -lc
dl_resolve_using = dl_findfile('-lc') if $dlsrc eq dl_dld.xs;
What causes memory leaks during graceful restarts?
All this talk about memory leakage has got me to wondering more about a problem I've noticed with mod_perl ever since I started using it: the more times you gracefully restart, the more memory you lose. This doesn't seem to be a result of the type of leakage that's being discussed in the other thread (which refers more to leakage and growth as the child runs normally) but is on such a large scale that I can only conclude that it's much more fundamental. For example, here's what an httpd process looks like having just restarted it from scratch: httpd 9063 0.0 6.6 19212 17020 ? S11:26 0:00 /usr/sbin/httpd -DSSL and here's what happens after one graceful restart: httpd 9092 0.0 9.2 25836 23644 ? S11:27 0:00 /usr/sbin/httpd -DSSL Where did those 6.5 Mb go? This is without making any requests from the server, so my mod_perl code isn't even being run, beyond initialization. (I use a PerlRequire to load a bunch of libraries at startup.) Are there any FAQs that address the reason for such large leakage? Or is this just an unavoidable problem with graceful restarts? Dan Wilga [EMAIL PROTECTED] Web Technology Specialist http://www.mtholyoke.edu Mount Holyoke CollegeTel: 413-538-3027 South Hadley, MA 01075 Who left the cake out in the rain?
Re: What causes memory leaks during graceful restarts?
what version of perl? what modperl Makefile.PL options? if you're using modperl as a dso, you'll need at least perl 5.6.1 and modperl-1.26 to prevent this leakage on restarts.
Re: What causes memory leaks during graceful restarts?
At 10:34 AM -0700 5/21/02, Doug MacEachern wrote: what version of perl? what modperl Makefile.PL options? if you're using modperl as a dso, you'll need at least perl 5.6.1 and modperl-1.26 to prevent this leakage on restarts. I am using Perl 5.6.1, modperl 1.25, and yes it's a DSO. It's compiled with: USE_APACI=1 SSL_BASE=/usr/local/ssl DO_HTTPD=1 So I guess the solution is to go to 1.26 or newer; I'll try that later in the week. Dan Wilga [EMAIL PROTECTED] Web Technology Specialist http://www.mtholyoke.edu Mount Holyoke CollegeTel: 413-538-3027 South Hadley, MA 01075Got Perl?
Re: What causes memory leaks during graceful restarts?
At 02:15 PM 5/21/02 -0400, Dan Wilga wrote: I am using Perl 5.6.1, modperl 1.25, and yes it's a DSO. It's compiled with: USE_APACI=1 SSL_BASE=/usr/local/ssl DO_HTTPD=1 So I guess the solution is to go to 1.26 or newer; I'll try that later in the week. Or to just compile mod_perl statically. Unless you need the ability to dynamically add in mod_perl, static is better. I'm sure the guide has all kinds of info about the tradeoffs of DSO vs. static. == Drew Taylor | Freelance web development using http://www.drewtaylor.com/ | perl/mod_perl/MySQL/postgresql/DBI mailto:[EMAIL PROTECTED] | Email jobs at drewtaylor.com -- Speakeasy.net: A DSL provider with a clue. Sign up today. http://www.speakeasy.net/refer/29655 ==
Re: What causes memory leaks during graceful restarts?
On Tue, 21 May 2002, Dan Wilga wrote: I am using Perl 5.6.1, modperl 1.25, and yes it's a DSO. It's compiled with: with 1.25, you can also set the PERL_DESTRUCT_LEVEL environment variable to 2, either before starting the server: export PERL_DESTRUCT_LEVEL=2 apachectl start or using PerlSetEnv in httpd.conf the fix in modperl-1.26 is simply to use that value by default.
