Re: speeding up XS_DBI_dispatch()

On 11/02/2012 00:48, Jan Dubois wrote:
> On Fri, 10 Feb 2012, Dave Mitchell wrote:
>> On Thu, Feb 09, 2012 at 11:10:17PM +0100, demerphq wrote:
>>> Well perls fork() relies on threaded  perl so it could very easily be
>>> Dave's patch. Dave do you have access to a win32 build environment?
>> I'm afraid not.
> The problem is due to the getenv() call during interpreter cloning.
> On Windows Perl keeps a virtual host environment for each interpreter,
> with its own cwd, and its own set of environment variables.  I don't
> have time to figure out _why_ this is an issue, but maybe you can check
> the environment variable during the BOOT section and just set a global
> variable instead, to work around this issue?
>
>      if (getenv("PERL_DBI_XSBYPASS"))
>          use_xsbypass = atoi(getenv("PERL_DBI_XSBYPASS"));
>
> On my old Windows 2000 system the test would simply abort with the
> message "abnormal program termination".  I was just guessing that
> this is somehow triggered by the abort() function in the C runtime.
> Setting a breakpoint on it confirms it, even though the stack trace
> looks incomplete (I don't see PerlEnvGetenv() calling abort() directly):
>
> MSVCRT!abort
> perl514!PerlEnvGetenv+0x13 [perlhost.h @ 462]
> DBI!dbi_bootinit+0x276 [DBI.xs @ 468]
> DBI!XS_DBI__clone_dbis+0x71 [DBI.c @ 4280]
> perl514!Perl_pp_entersub+0x701 [..\pp_hot.c @ 3049]
> perl514!Perl_runops_standard+0xc [..\run.c @ 41]
> perl514!Perl_call_sv+0x195 [perl.c @ 2633]
> perl514!perl_clone_using+0x18ad [..\sv.c @ 13422]
> perl514!PerlProcFork+0x89 [perlhost.h @ 1854]
> perl514!Perl_pp_fork+0x42 [..\pp_sys.c @ 4044]
> perl514!Perl_runops_standard+0xc [..\run.c @ 41]
> perl514!S_run_body+0xf5 [perl.c @ 2351]
> perl514!perl_run+0x179 [perl.c @ 2269]
> perl514!RunPerl+0xed [perllib.c @ 270]
> perl!main+0x12 [perlmain.c @ 22]
> perl!mainCRTStartup+0xe3
> KERNEL32!BaseProcessStart+0x3d
>
> Anyways, I would suggest trying a workaround by moving the getenv()
> call outside the cloning operation.
>
> Cheers,
> -Jan
>
>
Nice find Jan. Commenting out the getenv works for me.

Martin