Reply-To: "Jonathan Leffler" From: "Jonathan Leffler" To: Subject: Re: FW: [PHP-DEV] Bug #4468: random ifx_pconnect code -439 withifx_connect Date: Sat, 17 Jun 2000 10:01:13 +1300 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2911.0) In-Reply-To: <009101bfc6eb$4d4cb470$0101a8c0@csi.co.nz> X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Importance: Normal X-Sender: jleffler@anubis On Fri, 26 May 2000, Andrej Falout wrote: >Dear Jonathan, > >I hope you will forgive me for contacting you directly. Danny Heijl >and me are members of PHP development team. We are experiencing >problem described later, related to Informix ESQL/C and are not sure >how to interpret this. You aren't forgotten! >I tried calling support, but they have very few references to error >- -439 in there database. Also attached is code for Informix PHP >interface. > >Since I know you are the expert in this field, all PHP/Informix >community would be grateful to you if you would take a look and maybe >suggest where to start. It's not particularly easy to follow the code. The bug report is specifically to do with ifx_pconnect(), so the first section of the first function should be what needs scrutiny. Now, I can see where you look to see whether there is a connection for the same database/host, user and password, but I don't see where you verify whether that connection is in use at the moment. So, if you time it right and the same host/user/password combination is requested at the same time, then you might end up with two processes both trying to use the same connection, which won't work and will yield -439. Now, what am I overlooking? Where do you verify that the connection is not currently in use? >- -----Original Message----- >From: Danny Heijl [mailto:danny.heijl@cevi.be] >Sent: Sunday, 21 May 2000 9:36 >To: afalout@ihug.co.nz; pgrenier@framfab.fr; php-dev@lists.php.net >Subject: Re: [PHP-DEV] Bug #4468: random ifx_pconnect code -439 with >ifx_connect > > >As there are no signal handling routines in the php_ifx driver (it is >all strictly synchronous) I am beginning to suspect a problem in the >ESQL/C libraries when a lot of connecting/disconnecting is going on. > >Perhaps internal ESQL/C data structures are not getting released >immediately and make the ESQL/C libraries complain when the *same >process* tries to reopen the same connection that was closed only >milliseconds ago. > >I have several production sites running Apache/modphp3/Informix on >SVR4.0 Unix machines and have never experienced this error. They use >both local databases (using Streams Pipes IPC connections) and >databases on other machines (using TLI TCP connections ). > >But we *always* use persistent connections and force freeing of all >result sets (the ifx_ functions are wrapped in database/recordset >classes and are never called directly). As an aside, I can see no >obvious reasons for not using persistent connections. > >We have the same apps running on Windows NT 4 / IIS 4 with php 3.0.14 >as CGI too, no problems there either. But in CGI mode it is of course >*another* process that is opening that connection again. > >Perhaps our load is not big enough? Or the Informix libraries (IDS >7.22, IDS 7.23, or IDS 7.31, all with CSDK 2.30) on Windows and NCR >MP-RAS Unix do not have this problem? > >Danny >- --- > >- ----- Original Message ----- >From: "Andrej Falout" >To: ; >Cc: >Sent: Sunday, May 21, 2000 8:46 AM >Subject: RE: [PHP-DEV] Bug #4468: random ifx_pconnect code -439 with >ifx_connect > > >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA1 >> >> I was stress testing our installation, and on heavy CPU load we do get >> this too. >> >> - -439 >> >> Database server is currently processing an SQL task. >> >> You attempted to call an SQL routine or attempted to execute an SQL >> statement within a signal handling function/routine or a callback >> function/procedure. Use only the sqldone() and sqlbreak() library >> functions inside your INFORMIX-ESQL/C callback function. In >> addition, if you want to unregister your callback function in >> INFORMIX-ESQL/C, you can invoke the sqlbreakcallback() callback >> registration function within your callback procedure. >> >> I went trough all the usual suspects in ONCONFIG, but did not manage >> to get rid of it. From code description, it would look like problem in >> ESQL code of PHP Informix interface. Yes, it is a client-side (meaning PHP) problem rather than a server side problem. I wouldn't expect the ONCONFIG file to solve it at all. >> ifx.allow_persistent seems to reduce this, so I was playing with >> NETTYPE, but nothing definitive. Granted, I was really STRESSING the >> box. Are you closing your connections when finished, and freeing the >> results? >> >> >> > -----Original Message----- >> > From: pgrenier@framfab.fr [mailto:pgrenier@framfab.fr] >> > Sent: Wednesday, 17 May 2000 1:24 >> > To: php-dev@lists.php.net >> > Subject: [PHP-DEV] Bug #4468: random ifx_pconnect code -439 with ifx_connect >> > >> > >> > From: pgrenier@framfab.fr >> > Operating system: linux red hat 6.0 >> > PHP version: 3.0.14 >> > PHP Bug Type: Other >> > Bug description: random ifx_pconnect code -439 with ifx_connect >> > >> > configure php : >> > #!/bin/bash >> > CC="gcc" OPTIM="-O2" \ >> > ./configure \ >> > --includedir=/opt/informix/incl/esql \ >> > --with-apache=/www/install/apache_1.3.11 \ >> > --with-informix=/opt/informix \ >> > --with-zlib \ >> > --enable-sysvsem \ >> > --enable-sysvshm \ >> > --enable-track-vars \ >> > --enable-magic-quotes >> > >> > a piece of php3.ini : >> > [Informix] >> > ifx.default_host = ; default host >> > for ifx_connect() (doesn't apply in safe mode) >> > ifx.default_user = ; default user >> > for ifx_connect() (doesn't apply in safe mode) >> > ifx.default_password = ; default >> > password for ifx_connect() (doesn't apply in safe mode) >> > ifx.allow_persistent = Off ; allow or >> > prevent persistent link >> > ifx.max_persistent = -1 ; maximum number >> > of persistent links. -1 means no limit >> > ifx.max_links = -1 ; maximum number >> > of links (persistent+non persistent). -1 means no limit >> > ifx.textasvarchar = 0 ; if set on, >> > select statements return the contents of a text blob instead of it's id >> > ifx.byteasvarchar = 0 ; if set on, >> > select statements return the contents of a byte blob instead of it's id >> > ifx.charasvarchar = 0 ; trailing blanks >> > are stripped from fixed-length char columns. May help the life >> > ; of Informix SE users. >> > ifx.blobinfile = 0 ; if set on, the >> > contents of text&byte blobs are dumped to a file instead of >> > ; keeping them in memory >> > ifx.nullformat = 0 ; NULL's are >> > returned as empty strings, unless this is set to 1. In that case, >> > ; NULL's are returned as string 'NULL'. -- Yours, Jonathan Leffler (Jonathan.Leffler@Informix.com) #include Guardian of DBD::Informix v1.00.PC1 -- http://www.perl.com/CPAN "I don't suffer from insanity; I enjoy every minute of it!"