[SOLVED] Trying to create an SQL Query that will max all CPUs to 100%

Trying to create an SQL Query that will max all CPUs to 100%

As part of a stress tests I'm doing I'm trying to figure out if there is an SQL query (quite specifically SQL Server query) that will max all CPUs usage to 100% or close enough.

Suggestions anyone?

Solution

SELECT SUM(CONVERT(BIGINT, o1.object_id) + CONVERT(BIGINT, o2.object_id) + CONVERT(BIGINT, o3.object_id) + CONVERT(BIGINT, o4.object_id))
FROM sys.objects o1
CROSS JOIN sys.objects o2
CROSS JOIN sys.objects o3
CROSS JOIN sys.objects o4

Here's a parallel version:

USE master

SELECT MyInt = CONVERT(BIGINT, o1.object_id) + CONVERT(BIGINT, o2.object_id) + CONVERT(BIGINT, o3.object_id)
INTO #temp
FROM sys.objects o1
JOIN sys.objects o2 ON o1.object_id < o2.object_id
JOIN sys.objects o3 ON o1.object_id < o3.object_id

SELECT SUM(CONVERT(BIGINT, o1.MyInt) + CONVERT(BIGINT, o2.MyInt))
FROM #temp o1
JOIN #temp o2 ON o1.MyInt < o2.MyInt

For some reason I cannot get the optimizer to parallelize the first query. So I just materialize some huge tables (~400k rows) and loop join them.