in reply to Re^4: DBIx::Class and Parallel SQLite Transactions
in thread DBIx::Class and Parallel SQLite Transactions

I see no mention of threads and forking in the DBD::SQLite documentation. Grepping the source also lists no mention of threads in the SQLite.xs file, but only within sqlite3.c itself. This indicates to me that little thought has been given to how to make DBD::SQLite and threads/fork play nice together.

You can maybe check whether the problem is inherent to fork() and/or threads by launching multiple writes as real, separate processes via exec resp. system instead of fork/threads. If you still experience the segfaults/crashes, the problem likely is with your version of DBD::SQLite or some other XS code loaded in the separate process. If the problem goes away, then the problem likely is related to fork/threads and I see no other way than to change to a different DBD if you want to keep going with fork/threads.

You haven't told us your OS so far, but if you are on Windows, threads and fork() are basically the same thing there anyway, and all problems with one system are present in the other as well.

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Re^6: DBIx::Class and Parallel SQLite Transactions
by learnedbyerror (Monk) on Jul 14, 2011 at 14:38 UTC

    I'll take a shot a testing this evening.

    Sorry for forgetting the obvious. My primary environment is currently Fedora 13

    
    uname -a
    2.6.18-194.26.1.el5.028stab079.2 #1 SMP Fri Dec 17 19:25:15 MSK 2010 x86_64 x86_64 x86_64 GNU/Linux.

    My perl version info is:

    
    Summary of my perl5 (revision 5 version 10 subversion 1) configuration:
    
      Platform:
        osname=linux, osvers=2.6.32-71.14.1.el6.x86_64, archname=x86_64-linux-thread-multi
        uname='linux x86-06.phx2.fedoraproject.org 2.6.32-71.14.1.el6.x86_64 #1 smp wed jan 5 17:01:01 est 2011 x86_64 x86_64 x86_64 gnulinux '
        config_args='-des -Doptimize=-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -Dccdlflags=-Wl,--enable-new-dtags -DDEBUGGING=-g -Dversion=5.10.1 -Dmyhostname=localhost -Dperladmin=root@localhost -Dcc=gcc -Dcf_by=Red Hat, Inc. -Dprefix=/usr -Dvendorprefix=/usr -Dsiteprefix=/usr/local -Dsitelib=/usr/local/share/perl5 -Dsitearch=/usr/local/lib64/perl5 -Dprivlib=/usr/share/perl5 -Dvendorlib=/usr/share/perl5 -Darchlib=/usr/lib64/perl5 -Dvendorarch=/usr/lib64/perl5 -Dinc_version_list=5.10.0 -Darchname=x86_64-linux-thread-multi -Dlibpth=/usr/local/lib64 /lib64 /usr/lib64 -Duseshrplib -Dusethreads -Duseithreads -Duselargefiles -Dd_dosuid -Dd_semctl_semun -Di_db -Ui_ndbm -Di_gdbm -Di_shadow -Di_syslog -Dman3ext=3pm -Duseperlio -Dinstallusrbinperl=n -Ubincompat5005 -Uversiononly -Dpager=/usr/bin/less -isr -Dd_gethostent_r_proto -Ud_endhostent_r_proto -Ud_sethostent_r_proto -Ud_endprotoent_r_proto -Ud_setprotoent_r_proto -Ud_endservent_r_proto -Ud_setservent_r_proto -Dscriptdir=/usr/bin -Dotherlibdirs=/usr/local/lib64/perl5/site_perl/5.10.0/x86_64-linux-thread-multi:/usr/local/lib/perl5/site_perl/5.10.0:/usr/lib64/perl5/vendor_perl/5.10.0/x86_64-linux-thread-multi:/usr/lib/perl5/vendor_perl:/usr/lib/perl5/site_perl'
        hint=recommended, useposix=true, d_sigaction=define
        useithreads=define, usemultiplicity=define
        useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
        use64bitint=define, use64bitall=define, uselongdouble=undef
        usemymalloc=n, bincompat5005=undef
      Compiler:
        cc='gcc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
        optimize='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic',
        cppflags='-D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include'
        ccversion='', gccversion='4.4.5 20101112 (Red Hat 4.4.5-2)', gccosandvers=''
        intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
        d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
        ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
        alignbytes=8, prototype=define
      Linker and Libraries:
        ld='gcc', ldflags =' -fstack-protector'
        libpth=/usr/local/lib64 /lib64 /usr/lib64
        libs=-lresolv -lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lpthread -lc
        perllibs=-lresolv -lnsl -ldl -lm -lcrypt -lutil -lpthread -lc
        libc=, so=so, useshrplib=true, libperl=libperl.so
        gnulibc_version='2.12.2'
      Dynamic Linking:
        dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,--enable-new-dtags -Wl,-rpath,/usr/lib64/perl5/CORE'
        cccdlflags='-fPIC', lddlflags='-shared -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic'
    
    
    Characteristics of this binary (from libperl):
      Compile-time options: MULTIPLICITY PERL_DONT_CREATE_GVSV
                            PERL_IMPLICIT_CONTEXT PERL_MALLOC_WRAP USE_64_BIT_ALL
                            USE_64_BIT_INT USE_ITHREADS USE_LARGE_FILES
                            USE_PERLIO USE_REENTRANT_API
      Built under linux
      Compiled at Apr  5 2011 08:00:50
      %ENV:
        PERL_MM_USE_DEFAULT="1"
      @INC:
        /usr/local/lib64/perl5
        /usr/local/share/perl5
        /usr/lib64/perl5
        /usr/share/perl5
        /usr/lib64/perl5
        /usr/share/perl5
        /usr/local/lib64/perl5/site_perl/5.10.0/x86_64-linux-thread-multi
        /usr/local/lib/perl5/site_perl/5.10.0
        /usr/lib64/perl5/vendor_perl/5.10.0/x86_64-linux-thread-multi
        /usr/lib/perl5/vendor_perl/5.10.0
        /usr/lib/perl5/vendor_perl
        /usr/lib/perl5/site_perl