I ran valgrind –tool=callgrind on mserver5 while executing TPCH Q1 (in SQL) on a scale factor 100 database on a dual-processor, x86_64 linux server. The program failed due to an assertion in DELTAproject, namely assert(tres) on line 3614 in sql.mx. Without valgrind, the query completes correctly when mserver5 is run from a similar command line. What appears below is the valgrind program output. Steve Morgan ==1800== Callgrind, a call-graph generating cache profiler ==1800== Copyright (C) 2002-2011, and GNU GPL'd, by Josef Weidendorfer et al. ==1800== Using Valgrind-3.7.0 and LibVEX; rerun with -h for copyright info ==1800== Command: /usr/local/bin/mserver5 --dbpath=/home/ubuntu/monet/dbfarm/tpch --set merovingian_uri=mapi:monetdb://SM-MoDB3:50000/tpch --set mapi_open=false --set mapi_port=0 --set mapi_usock=/home/ubuntu/monet/dbfarm/tpch/.mapi.sock --set monet_vault_key=/home/ubuntu/monet/dbfarm/tpch/.vaultkey --set gdk_nr_threads=32 --set max_clients=64 --set sql_optimizer=default_pipe --set monet_daemon=yes ==1800== ==1800== For interactive control, run 'callgrind_control -h'. # MonetDB 5 server v11.15.3 "Feb2013-SP1" # Serving database 'tpch', using 32 threads # Compiled for x86_64-unknown-linux-gnu/64bit with 64bit OIDs dynamically linked # Found 188.887 GiB available main-memory. # Copyright (c) 1993-July 2008 CWI. # Copyright (c) August 2008-2013 MonetDB B.V., all rights reserved # Visit http://www.monetdb.org/ for further information # Listening for UNIX domain connection requests on mapi:monetdb:///home/ubuntu/monet/dbfarm/tpch/.mapi.sock # MonetDB/GIS module loaded # MonetDB/JAQL module loaded # MonetDB/SQL module loaded #GDKmalloc(116404584) fails, try to free up space [memory in use=4416764392,virtual memory in use=31869532648] #GDKmalloc(116404584) result [mem=3251134360,vm=15052332952] #GDKmallocmax: recovery ok. Continuing.. #GDKmmap(1600192512) fails, try to free up space [memory in use=8024487008,virtual memory in use=26927363168] #GDKmmap(1600192512) result [mem=5046231544,vm=20698587640] #GDKmmap: recovery ok. Continuing.. #GDKmmap(1600192512) fails, try to free up space [memory in use=5046232200,virtual memory in use=20898866312] #GDKmmap(1600192512) fails, try to free up space [memory in use=5046232200,virtual memory in use=22499058824] #GDKmmap(1600192512) result [mem=4897637384,vm=22350464008] mserver5: ../../../../MonetDB/sql/backends/monet5/sql.mx:3614: DELTAproject: Assertion `tres' failed. #GDKmmap(1600192512) result [mem=5097655904,vm=22550482528] #GDKmmap(1600192512) result [mem=5097655904,vm=22550482528] ==1800== ==1800== Events : Ir ==1800== Collected : 142458949886 ==1800== ==1800== I refs: 142,458,949,886 ./out: line 1: 1800 Killed valgrind --tool=callgrind /usr/local/bin/mserver5 --dbpath=/home/ubuntu/monet/dbfarm/tpch --set merovingian_uri=mapi:monetdb://SM-MoDB3:50000/tpch --set mapi_open=false --set mapi_port=0 --set mapi_usock=/home/ubuntu/monet/dbfarm/tpch/.mapi.sock --set monet_vault_key=/home/ubuntu/monet/dbfarm/tpch/.vaultkey --set gdk_nr_threads=32 --set max_clients=64 --set sql_optimizer=default_pipe --set monet_daemon=yes