I haven't tried it but you could probably modify the code I posted to test it. With the statement handle after 120(?) loops of apparent memory leak +1, there is a correction of -119.
Good luck. Steve. On 28 May 2015 05:00, "Duncan McEwan" <dun...@ecs.vuw.ac.nz> wrote: > Apologies for butting in on this thread, but I saw the following response > from Tim recently and it made me wonder ... > > On Tue, 26 May 2015 14:13:05 +0100 Tim Bunce <tim.bu...@pobox.com> wrote: > > > I've added this as a note: > > > > Note that the ChildHandles array holds weak references and that 'from > > time to time' the old slots get freed up. This isn't a leak, it just > > appears to be if you're not familiar with the caching that DBI does > > internally. You can rest assured that if the DBI did have a real leak > > a) a great many people would be affected and b) it would get fixed > very > > quickly. > > > > I think 'from time to time' is every 120 or so newly created child > handles. > > A while ago we had a mysterious problem using DBI in an application that > was > written as a plugin for the foswiki platform. Since our foswiki instance > was > running persistently under fcgid it was long-running and over time we'd > see a > gradual increase in the open connections it held to our mysql database > server. Eventually our server would reach it's maximum connection count > and > reject new connections. > > The most recent time I tried to debug this was over a year ago (March 2014) > and there was a brief exchange of emails on this list with the subject "DBI > Mysql Driver Handle Mysteriously Changes". > > Since then we've given up (!) and changed the way our application ran so it > is no longer a foswiki plugin. That seems to have "fixed" the connection > leakage and so we are unlikely to ever go back to find out exactly what was > going on here. > > But seeing this response from Tim about the fact that the DBI can cache up > to > 120 or so handles made me wonder if this is true for database handles as > well > as statement handles? Is it possible that our "problem" was simply the > correctly working DBI caching misbehaving due to our application running > persistently in multiple fcgid processes. > > I'm not looking to re-open investigating this issue - our environement has > now changed sufficiently that recreating the set up with the connection > leak > to do more debugging would be quite difficult. But I was just curious > about > whether the above could be the case. If the answer is "no" I'll be happy > to > just leave it at that! > > Thanks. > > Duncan >
