Re: BUG #5269: postgres backend terminates with SIGSEGV - Mailing list pgsql-bugs

Sorry for the delay.

I am attempting to construct a JDBC test case that reproduces the problem.

I have installed the patch and have not seen the crash since.

On Jan 13, 2010, at 11:58 AM, Tom Lane wrote:

> I wrote:
>> After puzzling over this for many hours, I have a theory that seems to
>> fit the facts.
>
> I think the attached patch will fix it for you --- please test.
>
>             regards, tom lane
>
> Index: src/backend/utils/cache/plancache.c
> ===================================================================
> RCS file: /cvsroot/pgsql/src/backend/utils/cache/plancache.c,v
> retrieving revision 1.27.2.1
> diff -c -r1.27.2.1 plancache.c
> *** src/backend/utils/cache/plancache.c    14 Jul 2009 15:37:55 -0000    1.27.2.1
> --- src/backend/utils/cache/plancache.c    13 Jan 2010 16:46:07 -0000
> ***************
> *** 1050,1063 ****
>  void
>  ResetPlanCache(void)
>  {
> !     ListCell   *lc;
>
> !     foreach(lc, cached_plans_list)
>      {
> !         CachedPlanSource *plansource = (CachedPlanSource *) lfirst(lc);
>          CachedPlan *plan = plansource->plan;
>
> !         if (plan)
> !             plan->dead = true;
>      }
>  }
> --- 1050,1106 ----
>  void
>  ResetPlanCache(void)
>  {
> !     ListCell   *lc1;
>
> !     foreach(lc1, cached_plans_list)
>      {
> !         CachedPlanSource *plansource = (CachedPlanSource *) lfirst(lc1);
>          CachedPlan *plan = plansource->plan;
> +         ListCell   *lc2;
>
> !         /* No work if it's already invalidated */
> !         if (!plan || plan->dead)
> !             continue;
> !
> !         /*
> !          * We *must not* mark transaction control statements as dead,
> !          * particularly not ROLLBACK, because they may need to be executed in
> !          * aborted transactions when we can't revalidate them (cf bug #5269).
> !          * In general there is no point in invalidating utility statements
> !          * since they have no plans anyway.  So mark it dead only if it
> !          * contains at least one non-utility statement.
> !          */
> !         if (plan->fully_planned)
> !         {
> !             /* Search statement list for non-utility statements */
> !             foreach(lc2, plan->stmt_list)
> !             {
> !                 PlannedStmt *plannedstmt = (PlannedStmt *) lfirst(lc2);
> !
> !                 Assert(!IsA(plannedstmt, Query));
> !                 if (IsA(plannedstmt, PlannedStmt))
> !                 {
> !                     /* non-utility statement, so invalidate */
> !                     plan->dead = true;
> !                     break;        /* out of stmt_list scan */
> !                 }
> !             }
> !         }
> !         else
> !         {
> !             /* Search Query list for non-utility statements */
> !             foreach(lc2, plan->stmt_list)
> !             {
> !                 Query       *query = (Query *) lfirst(lc2);
> !
> !                 Assert(IsA(query, Query));
> !                 if (query->commandType != CMD_UTILITY)
> !                 {
> !                     /* non-utility statement, so invalidate */
> !                     plan->dead = true;
> !                     break;        /* out of stmt_list scan */
> !                 }
> !             }
> !         }
>      }
>  }