/*
* dumptuples - remove tuples from memory and write to tape
*
* As a side effect, we must set readpos and markpos to the value
* corresponding to "current"; otherwise, a dump would lose the current read
* position.
*/
static void
dumptuples(Tuplestorestate *state, TuplestorePos *pos)
{
int i;
for (i = 0;; i++)
{
if (i == pos->current)
BufFileTell(state->myfile,
&pos->readpos_offset);
if (i == pos->markpos_current)
BufFileTell(state->myfile,
&pos->markpos_offset);
if (i >= state->memtupcount)
break;
WRITETUP(state, pos, state->memtuples[i]);
}
state->memtupcount = 0;
}
/*
* dumptuples - remove tuples from memory and write to tape
*
* As a side effect, we must convert each read pointer's position from
* "current" to file/offset format. But eof_reached pointers don't
* need to change state.
*/
static void
dumptuples(Tuplestorestate *state)
{
int i;
for (i = 0;; i++)
{
TSReadPointer *readptr = state->readptrs;
int j;
for (j = 0; j < state->readptrcount; readptr++, j++)
{
if (i == readptr->current && !readptr->eof_reached)
BufFileTell(state->myfile,
&readptr->file, &readptr->offset);
}
if (i >= state->memtupcount)
break;
WRITETUP(state, state->memtuples[i]);
}
state->memtupcount = 0;
}
static void
tuplestore_puttuple_common(Tuplestorestate *state, void *tuple)
{
TSReadPointer *readptr;
int i;
ResourceOwner oldowner;
state->tuples++;
switch (state->status)
{
case TSS_INMEM:
/*
* Update read pointers as needed; see API spec above.
*/
readptr = state->readptrs;
for (i = 0; i < state->readptrcount; readptr++, i++)
{
if (readptr->eof_reached && i != state->activeptr)
{
readptr->eof_reached = false;
readptr->current = state->memtupcount;
}
}
/*
* Grow the array as needed. Note that we try to grow the array
* when there is still one free slot remaining --- if we fail,
* there'll still be room to store the incoming tuple, and then
* we'll switch to tape-based operation.
*/
if (state->memtupcount >= state->memtupsize - 1)
{
(void) grow_memtuples(state);
Assert(state->memtupcount < state->memtupsize);
}
/* Stash the tuple in the in-memory array */
state->memtuples[state->memtupcount++] = tuple;
/*
* Done if we still fit in available memory and have array slots.
*/
if (state->memtupcount < state->memtupsize && !LACKMEM(state))
return;
/*
* Nope; time to switch to tape-based operation. Make sure that
* the temp file(s) are created in suitable temp tablespaces.
*/
PrepareTempTablespaces();
/* associate the file with the store's resource owner */
oldowner = CurrentResourceOwner;
CurrentResourceOwner = state->resowner;
state->myfile = BufFileCreateTemp(state->interXact);
CurrentResourceOwner = oldowner;
/*
* Freeze the decision about whether trailing length words will be
* used. We can't change this choice once data is on tape, even
* though callers might drop the requirement.
*/
state->backward = (state->eflags & EXEC_FLAG_BACKWARD) != 0;
state->status = TSS_WRITEFILE;
dumptuples(state);
break;
case TSS_WRITEFILE:
/*
* Update read pointers as needed; see API spec above. Note:
* BufFileTell is quite cheap, so not worth trying to avoid
* multiple calls.
*/
readptr = state->readptrs;
for (i = 0; i < state->readptrcount; readptr++, i++)
{
if (readptr->eof_reached && i != state->activeptr)
{
readptr->eof_reached = false;
BufFileTell(state->myfile,
&readptr->file,
&readptr->offset);
}
}
WRITETUP(state, tuple);
break;
case TSS_READFILE:
/*
* Switch from reading to writing.
*/
if (!state->readptrs[state->activeptr].eof_reached)
BufFileTell(state->myfile,
&state->readptrs[state->activeptr].file,
&state->readptrs[state->activeptr].offset);
if (BufFileSeek(state->myfile,
state->writepos_file, state->writepos_offset,
SEEK_SET) != 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not seek in tuplestore temporary file: %m")));
state->status = TSS_WRITEFILE;
/*
* Update read pointers as needed; see API spec above.
*/
readptr = state->readptrs;
for (i = 0; i < state->readptrcount; readptr++, i++)
{
if (readptr->eof_reached && i != state->activeptr)
{
readptr->eof_reached = false;
readptr->file = state->writepos_file;
readptr->offset = state->writepos_offset;
}
}
WRITETUP(state, tuple);
break;
default:
elog(ERROR, "invalid tuplestore state");
break;
}
}
static void
tuplestore_puttuple_common(Tuplestorestate *state, TuplestorePos *pos, void *tuple)
{
ResourceOwner oldowner;
switch (state->status)
{
case TSS_INMEM:
/*
* Grow the array as needed. Note that we try to grow the array
* when there is still one free slot remaining --- if we fail,
* there'll still be room to store the incoming tuple, and then
* we'll switch to tape-based operation.
*/
if (state->memtupcount >= state->memtupsize - 1)
{
/*
* See grow_memtuples() in tuplesort.c for the rationale
* behind these two tests.
*/
if (state->availMem > (long) (state->memtupsize * sizeof(void *)) &&
(Size) (state->memtupsize * 2) < MaxAllocSize / sizeof(void *))
{
FREEMEM(state, GetMemoryChunkSpace(state->memtuples));
state->memtupsize *= 2;
state->memtuples = (void **)
repalloc(state->memtuples,
state->memtupsize * sizeof(void *));
USEMEM(state, GetMemoryChunkSpace(state->memtuples));
}
}
/* Stash the tuple in the in-memory array */
state->memtuples[state->memtupcount++] = tuple;
/* If eof_reached, keep read position in sync */
if (pos->eof_reached)
pos->current = state->memtupcount;
/*
* Done if we still fit in available memory and have array slots.
*/
if (state->memtupcount < state->memtupsize && !LACKMEM(state))
return;
/*
* Nope; time to switch to tape-based operation. Make sure that
* the temp file(s) are created in suitable temp tablespaces.
*/
PrepareTempTablespaces();
/* associate the file with the store's resource owner */
oldowner = CurrentResourceOwner;
CurrentResourceOwner = state->resowner;
{
char tmpprefix[50];
snprintf(tmpprefix, 50, "slice%d_tuplestore", currentSliceId);
state->myfile = BufFileCreateTemp(tmpprefix, state->interXact);
}
CurrentResourceOwner = oldowner;
state->status = TSS_WRITEFILE;
dumptuples(state, pos);
break;
case TSS_WRITEFILE:
WRITETUP(state, pos, tuple);
break;
case TSS_READFILE:
/*
* Switch from reading to writing.
*/
if (!pos->eof_reached)
BufFileTell(state->myfile,
&pos->readpos_offset);
if (BufFileSeek(state->myfile,
pos->writepos_offset,
SEEK_SET) != 0)
elog(ERROR, "seek to EOF failed");
state->status = TSS_WRITEFILE;
WRITETUP(state, pos, tuple);
break;
default:
elog(ERROR, "invalid tuplestore state");
break;
}
}
static void
tuplestore_puttuple_common(Tuplestorestate *state, void *tuple)
{
TSReadPointer *readptr;
int i;
ResourceOwner oldowner;
switch (state->status)
{
case TSS_INMEM:
/*
* Update read pointers as needed; see API spec above.
*/
readptr = state->readptrs;
for (i = 0; i < state->readptrcount; readptr++, i++)
{
if (readptr->eof_reached && i != state->activeptr)
{
readptr->eof_reached = false;
readptr->current = state->memtupcount;
}
}
/*
* Grow the array as needed. Note that we try to grow the array
* when there is still one free slot remaining --- if we fail,
* there'll still be room to store the incoming tuple, and then
* we'll switch to tape-based operation.
*/
if (state->memtupcount >= state->memtupsize - 1)
{
/*
* See grow_memtuples() in tuplesort.c for the rationale
* behind these two tests.
*/
if (state->availMem > (long) (state->memtupsize * sizeof(void *)) &&
(Size) (state->memtupsize * 2) < MaxAllocSize / sizeof(void *))
{
FREEMEM(state, GetMemoryChunkSpace(state->memtuples));
state->memtupsize *= 2;
state->memtuples = (void **)
repalloc(state->memtuples,
state->memtupsize * sizeof(void *));
USEMEM(state, GetMemoryChunkSpace(state->memtuples));
if (LACKMEM(state))
elog(ERROR, "unexpected out-of-memory situation in tuplestore");
}
}
/* Stash the tuple in the in-memory array */
state->memtuples[state->memtupcount++] = tuple;
/*
* Done if we still fit in available memory and have array slots.
*/
if (state->memtupcount < state->memtupsize && !LACKMEM(state))
return;
/*
* Nope; time to switch to tape-based operation. Make sure that
* the temp file(s) are created in suitable temp tablespaces.
*/
PrepareTempTablespaces();
/* associate the file with the store's resource owner */
oldowner = CurrentResourceOwner;
CurrentResourceOwner = state->resowner;
char tmpprefix[50];
snprintf(tmpprefix, 50, "slice%d_tuplestore", currentSliceId);
state->myfile = BufFileCreateTemp(tmpprefix, state->interXact);
CurrentResourceOwner = oldowner;
/*
* Freeze the decision about whether trailing length words will be
* used. We can't change this choice once data is on tape, even
* though callers might drop the requirement.
*/
state->backward = (state->eflags & EXEC_FLAG_BACKWARD) != 0;
state->status = TSS_WRITEFILE;
dumptuples(state);
break;
case TSS_WRITEFILE:
/*
* Update read pointers as needed; see API spec above. Note:
* BufFileTell is quite cheap, so not worth trying to avoid
* multiple calls.
*/
readptr = state->readptrs;
for (i = 0; i < state->readptrcount; readptr++, i++)
{
if (readptr->eof_reached && i != state->activeptr)
{
readptr->eof_reached = false;
BufFileTell(state->myfile,
&readptr->file,
&readptr->offset);
}
}
WRITETUP(state, tuple);
break;
case TSS_READFILE:
/*
* Switch from reading to writing.
*/
if (!state->readptrs[state->activeptr].eof_reached)
BufFileTell(state->myfile,
&state->readptrs[state->activeptr].file,
&state->readptrs[state->activeptr].offset);
if (BufFileSeek(state->myfile,
state->writepos_file, state->writepos_offset,
SEEK_SET) != 0)
elog(ERROR, "tuplestore seek to EOF failed");
state->status = TSS_WRITEFILE;
/*
* Update read pointers as needed; see API spec above.
*/
readptr = state->readptrs;
for (i = 0; i < state->readptrcount; readptr++, i++)
{
if (readptr->eof_reached && i != state->activeptr)
{
readptr->eof_reached = false;
readptr->file = state->writepos_file;
readptr->offset = state->writepos_offset;
}
}
WRITETUP(state, tuple);
break;
default:
elog(ERROR, "invalid tuplestore state");
break;
}
}