Changeset: c1c78349a3a4 for MonetDB
URL: http://dev.monetdb.org/hg/MonetDB?cmd=changeset;node=c1c78349a3a4
Modified Files:
sql/backends/monet5/sql_optimizer.c
Branch: default
Log Message:
Decide on optimizer pipeline
If the total footprint of the columns accessed in a query
exceed the available memory, then switch to the volcano_pipe
optimizer.
diffs (96 lines):
diff --git a/sql/backends/monet5/sql_optimizer.c
b/sql/backends/monet5/sql_optimizer.c
--- a/sql/backends/monet5/sql_optimizer.c
+++ b/sql/backends/monet5/sql_optimizer.c
@@ -35,7 +35,6 @@
/*
* Cost-based optimization and semantic evaluations require statistics to work
with.
* They should come from the SQL catalog or the BATs themselves.
- * The properties passed at this point are the number of rows.
* A better way is to mark all BATs used as a constant, because that permits
* access to all properties. However, this creates unnecessary locking during
stack
* initialization. Therfore, we store the BAT id as a property for the
optimizer
@@ -51,13 +50,14 @@
* common term optimizer, because the first bind has a side-effect.
*/
-static void SQLgetStatistics(Client cntxt, mvc *m, MalBlkPtr mb)
+static size_t SQLgetStatistics(Client cntxt, mvc *m, MalBlkPtr mb)
{
InstrPtr *old = NULL;
int oldtop, i, actions = 0, size = 0;
lng clk = GDKusec();
sql_trans *tr = m->session->tr;
str msg;
+ size_t space = 0; // sum the total amount of data potentially read
old = mb->stmt;
oldtop = mb->stop;
@@ -93,6 +93,7 @@ static void SQLgetStatistics(Client cntx
char *sname = getVarConstant(mb, getArg(p, 2 +
upd)).val.sval;
char *tname = getVarConstant(mb, getArg(p, 3 +
upd)).val.sval;
char *cname = NULL;
+
int mt_member = 0;
BUN rows = 1; /* default to cope with delta bats */
int mode = 0;
@@ -117,6 +118,10 @@ static void SQLgetStatistics(Client cntx
b =
store_funcs.bind_idx(m->session->tr, i, RDONLY);
if (b) {
cnt = BATcount(b);
+ if( mode == 0) {
+ space += getBatSpace(b);
+ //mnstr_printf(GDKout,
"#space estimate %s.%s.%s mode %d "LLFMT"\n",sname,tname,cname, mode,
getBatSpace(b));
+ }
BBPunfix(b->batCacheid);
}
rows = (BUN) cnt;
@@ -134,6 +139,10 @@ static void SQLgetStatistics(Client cntx
b =
store_funcs.bind_col(m->session->tr, c, RDONLY);
if (b) {
cnt = BATcount(b);
+ if( mode == 0) {
+ space += getBatSpace(b);
+ //mnstr_printf(GDKout,
"#space estimate %s.%s.%s mode %d "LLFMT"\n",sname,tname,cname, mode,
getBatSpace(b));
+ }
BBPunfix(b->batCacheid);
}
rows = (BUN) cnt;
@@ -155,6 +164,7 @@ static void SQLgetStatistics(Client cntx
msg = optimizerCheck(cntxt, mb, "optimizer.SQLgetstatistics", actions,
GDKusec() - clk);
if (msg) /* what to do with an error? */
GDKfree(msg);
+ return space;
}
str
@@ -175,11 +185,21 @@ addOptimizers(Client c, MalBlkPtr mb, ch
InstrPtr q;
backend *be;
str msg;
+ size_t space;
be = (backend *) c->sqlcontext;
assert(be && be->mvc); /* SQL clients should always have their state
set */
- msg = addOptimizerPipe(c, mb, pipe ? pipe : "default_pipe");
+ space = SQLgetStatistics(c, be->mvc, mb);
+ if(space && (pipe == NULL || strcmp(pipe,"default_pipe")== 0)){
+ if( space > MT_npages() * MT_pagesize()){
+ pipe = "volcano_pipe";
+ mnstr_printf(GDKout, "#use volcano optimizer pipeline?
"SZFMT"\n", space);
+ }else
+ pipe = "default_pipe";
+ } else
+ pipe = pipe? pipe: "default_pipe";
+ msg = addOptimizerPipe(c, mb, pipe);
if (msg)
GDKfree(msg); /* what to do with an error? */
/* point queries do not require mitosis and dataflow */
@@ -192,7 +212,6 @@ addOptimizers(Client c, MalBlkPtr mb, ch
q->token = REMsymbol; /* they are ignored */
}
}
- SQLgetStatistics(c, be->mvc, mb);
if (be->mvc->emod & mod_debug)
addtoMalBlkHistory(mb, "getStatistics");
}
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