I'm working on a daemon which does intermittent bursts of work and commits some of it to a PostgreSQL database. These bursts can sometimes be 10-15 minutes apart and the current bane of my existence is
DBD::Pg::db do failed: server closed the connection unexpectedly
        This probably means the server terminated abnormally
        before or while processing the request.

[download]
I assume this is a timeout issue, but all searches I've done (here, google, etc.) have just turned up information on using signals to set DBI/query timeouts, not how to prevent them. I have also attempted in vain to locate any way of changing/disabling connection idle timeouts via DBI, DBD::Pg, and the Postgres configuration.

I am also frequently seeing

message type 0x43 arrived from server while idle
message type 0x5a arrived from server while idle

[download]

The best I've been able to achieve so far is to do a $dbh->ping || initialize_database_connection(); right before going into my main processing, which mostly works, but, race conditions being what they are, I still get the DBD::Pg::db error on occasion when $dbh goes stale between the ping and the next query. I had actually been hoping that whatever test DBD::Pg->ping does would itself be enough to keep the connection alive, but no such luck.

Any suggestions on how to keep this db connection from going bad on me?

Update: After a suggestion from samtregar that this might not actually be a timeout issue, it turned out that I wasn't being careful enough when mixing fork and DBI. Thanks to all who offered ideas along the way.

In reply to Preventing database handles from going stale by dsheroh

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.