(cross-posted at the dancer.pm mail list http://lists.preshweb.co.uk/pipermail/dancer-users/2015-April/004537.html)

I'm building a site and it's all fine and well except when randomly getting part of the page (without any css,html) essentially like a semi-half blank page and ,sometimes again, getting a "Reload the page to get source for:" from the GET request using Firebug. Firebug's Net panels shows only the initial GET request but not the subsequent ones to the other resources, like the CSS file, images,Javascripts etc

When that happens I get the following in the DBI trace log : 

<-- dbd_st_finish
1   <- fetch= ( undef ) [1 items] row1 at /home/starman/perl5/perlbrew
+/perls/perl-5.18.1/lib/site_perl/5.18.1/x86_64-linux/DBD/mysql.pm lin
+e 867 via  at /home/starman/Foo/bin/../lib/MySite/Model.pm line 219
    <- fetchrow_hashref= ( undef ) [1 items] row1 at /home/starman/Foo
+/bin/../lib/MySite/Model.pm line 219 via  at /home/starman/Foo/bin/..
+/lib/Foo.pm line 34
    <> DESTROY(DBI::st=HASH(0x3fcfc60)) ignored for outer handle (inne
+r DBI::st=HASH(0x3fcfac8) has ref cnt 1)
    -> DESTROY for DBD::mysql::st (DBI::st=HASH(0x3fcfac8)~INNER)
    <- DESTROY= ( undef ) [1 items] at /home/starman/Foo/bin/../lib/Fo
+o.pm line 34 via  at /home/starman/Foo/bin/../lib/Foo.pm line 34
    DESTROY (dbih_clearcom) (sth 0x3fcfac8, com 0x41e4d70, imp DBD::my
+sql::st):
       FLAGS 0x180191: COMSET Warn RaiseError PrintError PrintWarn
       PARENT DBI::db=HASH(0x3d23dc0)
       KIDS 0 (0 Active)
       NUM_OF_FIELDS 38
       NUM_OF_PARAMS 0
    dbih_clearcom 0x3fcfac8 (com 0x41e4d70, type 3) done.

    <> DESTROY(DBI::db=HASH(0x3d18b00)) ignored for outer handle (inne
+r DBI::db=HASH(0x3d23dc0) has ref cnt 1)
    -> DESTROY for DBD::mysql::db (DBI::db=HASH(0x3d23dc0)~INNER)
imp_dbh->pmysql: 42d7440
    <- DESTROY= ( undef ) [1 items] at /home/starman/Foo/bin/../lib/Fo
+o.pm line 34 via  at /home/starman/Foo/bin/../lib/Foo.pm line 34
    DESTROY (dbih_clearcom) (dbh 0x3d23dc0, com 0x418e4e0, imp DBD::my
+sql::db):
       FLAGS 0x180391: COMSET Warn RaiseError PrintError PrintWarn Aut
+oCommit
       PARENT DBI::dr=HASH(0x3c85940)
       KIDS 0 (0 Active)
       IMP_DATA HASH(0x3d23478)
    dbih_clearcom 0x3d23dc0 (com 0x418e4e0, type 2) done.

[download]

I should explain more:
there are two queries each one in its own sub, the first one being called through a straightforward [% PROCESS tablets.tt %] which populates some elements like drop down select menus,sliders etc

When the user makes a choice the second query is fired through an Ajax call: 

$.ajax({
            url: '/query2',
            type: "POST",
            
            data: AllData(1)}).success(function(data){
                                $("#contentx").append(data);
                              });

[download]
which populates a #contentx div with the results of the query.

Now,when in the same session, the error does not occur no matter how much I stress it. When opening another 4-5 sessions,or doing a couple of reloads of the same session, the DBI error comes up and I get the effect of the first query being run as the elements are still populated, but then there is nothing else:no css,scripts,and the rest of the html code .

Is that indicating a global DBI handle that is reused and cleaned up at some time,having to do with Starman's preforking? The thing is that in my Model I initialize the database and statement handles within the subs scope and not globally.
Any help deeply appreciated,thanks!

The setup is Dancer,Starman,Mysql on Digital Ocean
DBD:mysql 4.031
DBI 1.633
Dancer2 0.158000
Ubuntu 14.04 x86_64 x86_64 x86_64 GNU/Linux

In reply to random web page breakages (Dancer2) by nikosv

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