MonetDB: mosaic - Protect against too many parallel threads

[Martin Kersten]

Changeset: d208fd9b2bff for MonetDB
URL: http://dev.monetdb.org/hg/MonetDB?cmd=changeset;node=d208fd9b2bff
Modified Files:
        monetdb5/modules/mal/mosaic.c
Branch: mosaic
Log Message:

Protect against too many parallel threads


diffs (59 lines):

diff --git a/monetdb5/modules/mal/mosaic.c b/monetdb5/modules/mal/mosaic.c
--- a/monetdb5/modules/mal/mosaic.c
+++ b/monetdb5/modules/mal/mosaic.c
@@ -658,6 +658,15 @@ MOSsubselect(Client cntxt, MalBlkPtr mb,
        // determine block range to scan for partitioned columns
        MOSgetPartition(cntxt, mb, stk, getArg(pci,1), &part, &nrofparts );
        if ( nrofparts > 1){
+               // don't use more parallelism then entries in the header
+               if( nrofparts > task->hdr->top)
+                       nrofparts = task->hdr->top;
+               if( part > nrofparts){
+                       * (bat *) getArgReference(stk, pci, 0) = bn->batCacheid;
+                       BBPkeepref(bn->batCacheid);
+                       GDKfree(task);
+                       return MAL_SUCCEED;
+               }
                startblk = task->hdr->top/nrofparts * part;
                if( part == nrofparts -1)
                        stopblk  =  task->hdr->top;
@@ -767,6 +776,7 @@ str MOSthetasubselect(Client cntxt, MalB
                if (cand == NULL){
                        BBPreleaseref(b->batCacheid);
                        BBPreleaseref(bn->batCacheid);
+                       GDKfree(task);
                        throw(MAL, "mosaic.thetasubselect", 
RUNTIME_OBJECT_MISSING);
                }
                task->cl = (oid*) Tloc(cand, BUNfirst(cand));
@@ -776,6 +786,14 @@ str MOSthetasubselect(Client cntxt, MalB
        // determine block range to scan for partitioned columns
        MOSgetPartition(cntxt, mb, stk, getArg(pci,1), &part, &nrofparts );
        if ( nrofparts > 1){
+               // don't use more parallelism then entries in the header
+               if( nrofparts > task->hdr->top)
+                       nrofparts = task->hdr->top;
+               if( part > nrofparts){
+                       BBPkeepref(*(int*)getArgReference(stk,pci,0)= 
bn->batCacheid);
+                       GDKfree(task);
+                       return MAL_SUCCEED;
+               }
                startblk = task->hdr->top/nrofparts * part;
                if( part == nrofparts -1)
                        stopblk  =  task->hdr->top;
@@ -890,6 +908,16 @@ str MOSleftfetchjoin(Client cntxt, MalBl
        // determine block range to scan for partitioned columns
        MOSgetPartition(cntxt, mb, stk, getArg(pci,1), &part, &nrofparts );
        if ( nrofparts > 1){
+               // don't use more parallelism then entries in the header
+               if( nrofparts > task->hdr->top)
+                       nrofparts = task->hdr->top;
+               if( part > nrofparts){
+                       BBPreleaseref(*lid);
+                       BBPreleaseref(*rid);
+                       BBPkeepref(*ret = bn->batCacheid);
+                       GDKfree(task);
+                       return MAL_SUCCEED;
+               }
                startblk = task->hdr->top/nrofparts * part;
                if( part == nrofparts -1)
                        stopblk  =  task->hdr->top;
_______________________________________________
checkin-list mailing list
checkin-list@monetdb.org
https://www.monetdb.org/mailman/listinfo/checkin-list