Re: shared tempfile was not removed on statement_timeout

On Mon, Jul 27, 2020 at 08:00:46PM +1200, Thomas Munro wrote:
> On Tue, Jul 21, 2020 at 4:33 PM Justin Pryzby <pryzby(at)telsasoft(dot)com> wrote:
> > /*
> > * clean up a spool structure and its substructures.
> > */
> > static void
> > _bt_spooldestroy(BTSpool *btspool)
> > {
> > + void *fileset = tuplesort_shared_fileset(btspool->sortstate);
> > + if (fileset)
> > + SharedFileSetDeleteAll(fileset);
> > tuplesort_end(btspool->sortstate);
> > pfree(btspool);
> > }
>
> Why can't tuplesort_end do it?

Because then I think the parallel workers remove their own files, with tests
failing like:

+ERROR: could not open temporary file "0.0" from BufFile "0": No such file or directory

I look around a bit more and came up with this, which works, but I don't know
enough to say if it's right.

diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index 5f6420efb2..f89d42f475 100644
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -3344,6 +3344,7 @@ walkdir(const char *path,
struct stat fst;
int sret;

+ usleep(99999);
CHECK_FOR_INTERRUPTS();

if (strcmp(de->d_name, ".") == 0 ||
diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 3c49476483..c6e5e6d00b 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -1387,6 +1387,9 @@ tuplesort_free(Tuplesortstate *state)
void
tuplesort_end(Tuplesortstate *state)
{
+ if (state->shared && state->shared->workersFinished == state->nParticipants)
+ SharedFileSetDeleteAll(&state->shared->fileset);
+
tuplesort_free(state);

/*