— Total waits are wait_time_ms (high signal waits indicates CPU pressure)
SELECT signal_wait_time_ms=SUM(signal_wait_time_ms)
,'signal (cpu) waits' = CAST(100.0 * SUM(signal_wait_time_ms) / SUM (wait_time_ms) AS NUMERIC(20,2))
,resource_wait_time_ms= SUM(wait_time_ms - signal_wait_time_ms)
,'%resource waits'= CAST(100.0 * SUM(wait_time_ms - signal_wait_time_ms) / SUM (wait_time_ms) AS NUMERIC(20,2))
FROM sys.dm_os_wait_stats

-- Check SQL Server Schedulers to see if they are waiting on CPU
-- If the runnable task count is above 10 for multiple schedulers, you are experiencing CPU pressure.
SELECT scheduler_id, current_tasks_count, runnable_tasks_count
FROM sys.dm_os_schedulers
WHERE scheduler_id < 255

SELECT
session_id,status,
command,sql_handle,database_id
,(SELECT text FROM sys.dm_exec_sql_text(sql_handle)) AS query_text
FROM sys.dm_exec_requests r
WHERE session_id >= 51

SELECT SERVERNAME SvrName, s.[Status], s.SPID, s.CPU, s.Physical_IO, s.WaitTime, s.Blocked,
Text LastCmd, SUBSTRING(s.HostName, 1, 36) HostName, SUBSTRING(s.Program_Name, 1, 100) PrgName,
SUBSTRING(s.nt_username, 1, 50) NtUserName, s.Login_Time, s.Last_Batch, s.Open_Tran
FROM master.dbo.sysprocesses s
CROSS APPLY ::fn_get_sql(s.sql_handle)
WHERE (blocked > 0
OR spid IN (SELECT blocked FROM master.dbo.sysprocesses (NOLOCK) WHERE blocked > 0)
OR open_tran > 0)
AND SPID <> SPID
AND Blocked > 0

2 ways:

Restart SQL server
DBCC SQLPERF (‘sys.dm_db_index_usage_stats’, clear)

SELECT COUNT(DISTINCT scheduler_id) AS TotalVisibleCores
FROM sys.dm_os_schedulers
WHERE scheduler_id < 1048576 — >= 1048576 = hidden

select cpu_count/hyperthread_ratio AS sockets from sys.dm_os_sys_info — How many sockets does my machine have?
select hyperthread_ratio AS cores_or_logical_cpus_per_socket from sys.dm_os_sys_info — How many either cores or logical CPU share the same socket?
select physical_memory_in_bytes/1024 AS physical_memory_in_kb from sys.dm_os_sys_info — How much physical memory my machine has?
select max_workers_count from sys.dm_os_sys_info — How many threads/workers SQL Server would use if the default value in sp_configure for max worker threads is zero:
select bpool_visible from sys.dm_os_sys_info — What is a size of AWE window or what is the max amount of memory right now that can be used by QO, QE and Caches simultaneously when SQL Server running in AWE mode?