it means you have buffer cache issue and IO contentions

see these links

http://www.sqlservercentral.com/articles/Performance+Tuning/analyzingmemoryrequirementsforsqlserver/2498/

http://sqlblog.com/blogs/buck_woody/archive/2010/06/29/the-windows-page-file-and-sql-server.aspx

http://support.microsoft.com/kb/889654/en-us

and take help from these

/**********************************************************

* top procedures memory consumption per execution

* (this will show mostly reports & jobs)

***********************************************************/

SELECT TOP 100 *

FROM

(

SELECT

DatabaseName = DB_NAME(qt.dbid)

,ObjectName = OBJECT_SCHEMA_NAME(qt.objectid,dbid) + '.' + OBJECT_NAME(qt.objectid, qt.dbid)

,DiskReads = SUM(qs.total_physical_reads) -- The worst reads, disk reads

,MemoryReads = SUM(qs.total_logical_reads) --Logical Reads are memory reads

,Executions = SUM(qs.execution_count)

,IO_Per_Execution = SUM((qs.total_physical_reads + qs.total_logical_reads) / qs.execution_count)

,CPUTime = SUM(qs.total_worker_time)

,DiskWaitAndCPUTime = SUM(qs.total_elapsed_time)

,MemoryWrites = SUM(qs.max_logical_writes)

,DateLastExecuted = MAX(qs.last_execution_time)

FROM sys.dm_exec_query_stats AS qs

CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS qt

GROUP BY DB_NAME(qt.dbid), OBJECT_SCHEMA_NAME(qt.objectid,dbid) + '.' + OBJECT_NAME(qt.objectid, qt.dbid)

) T

ORDER BY IO_Per_Execution DESC

/**********************************************************

* top procedures memory consumption total

* (this will show more operational procedures)

***********************************************************/

SELECT TOP 100 *

FROM

(

SELECT

DatabaseName = DB_NAME(qt.dbid)

,ObjectName = OBJECT_SCHEMA_NAME(qt.objectid,dbid) + '.' + OBJECT_NAME(qt.objectid, qt.dbid)

,DiskReads = SUM(qs.total_physical_reads) -- The worst reads, disk reads

,MemoryReads = SUM(qs.total_logical_reads) --Logical Reads are memory reads

,Total_IO_Reads = SUM(qs.total_physical_reads + qs.total_logical_reads)

,Executions = SUM(qs.execution_count)

,IO_Per_Execution = SUM((qs.total_physical_reads + qs.total_logical_reads) / qs.execution_count)

,CPUTime = SUM(qs.total_worker_time)

,DiskWaitAndCPUTime = SUM(qs.total_elapsed_time)

,MemoryWrites = SUM(qs.max_logical_writes)

,DateLastExecuted = MAX(qs.last_execution_time)

FROM sys.dm_exec_query_stats AS qs

CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS qt

GROUP BY DB_NAME(qt.dbid), OBJECT_SCHEMA_NAME(qt.objectid,dbid) + '.' + OBJECT_NAME(qt.objectid, qt.dbid)

) T

ORDER BY Total_IO_Reads DESC

/**********************************************************

* top adhoc queries memory consumption total

***********************************************************/

SELECT TOP 100 *

FROM

(

SELECT

DatabaseName = DB_NAME(qt.dbid)

,QueryText = qt.text

,DiskReads = SUM(qs.total_physical_reads) -- The worst reads, disk reads

,MemoryReads = SUM(qs.total_logical_reads) --Logical Reads are memory reads

,Total_IO_Reads = SUM(qs.total_physical_reads + qs.total_logical_reads)

,Executions = SUM(qs.execution_count)

,IO_Per_Execution = SUM((qs.total_physical_reads + qs.total_logical_reads) / qs.execution_count)

,CPUTime = SUM(qs.total_worker_time)

,DiskWaitAndCPUTime = SUM(qs.total_elapsed_time)

,MemoryWrites = SUM(qs.max_logical_writes)

,DateLastExecuted = MAX(qs.last_execution_time)

FROM sys.dm_exec_query_stats AS qs

CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS qt

WHERE OBJECT_SCHEMA_NAME(qt.objectid,dbid) + '.' + OBJECT_NAME(qt.objectid, qt.dbid) IS NULL

GROUP BY DB_NAME(qt.dbid), qt.text, OBJECT_SCHEMA_NAME(qt.objectid,dbid) + '.' + OBJECT_NAME(qt.objectid, qt.dbid)

) T

ORDER BY Total_IO_Reads DESC

/**********************************************************

* top adhoc queries memory consumption per execution

***********************************************************/

SELECT TOP 100 *

FROM

(

SELECT

DatabaseName = DB_NAME(qt.dbid)

,QueryText = qt.text

,DiskReads = SUM(qs.total_physical_reads) -- The worst reads, disk reads

,MemoryReads = SUM(qs.total_logical_reads) --Logical Reads are memory reads

,Total_IO_Reads = SUM(qs.total_physical_reads + qs.total_logical_reads)

,Executions = SUM(qs.execution_count)

,IO_Per_Execution = SUM((qs.total_physical_reads + qs.total_logical_reads) / qs.execution_count)

,CPUTime = SUM(qs.total_worker_time)

,DiskWaitAndCPUTime = SUM(qs.total_elapsed_time)

,MemoryWrites = SUM(qs.max_logical_writes)

,DateLastExecuted = MAX(qs.last_execution_time)

FROM sys.dm_exec_query_stats AS qs

CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS qt

WHERE OBJECT_SCHEMA_NAME(qt.objectid,dbid) + '.' + OBJECT_NAME(qt.objectid, qt.dbid) IS NULL

GROUP BY DB_NAME(qt.dbid), qt.text, OBJECT_SCHEMA_NAME(qt.objectid,dbid) + '.' + OBJECT_NAME(qt.objectid, qt.dbid)

) T

ORDER BY IO_Per_Execution DESC

AND

--Bpool stats

select (bpool_committed * 8192)/ (1024*1024) as bpool_committed_mb

, (cast(bpool_commit_target as bigint) * 8192) / (1024*1024) as bpool_target_mb,

(bpool_visible * 8192) / (1024*1024) as bpool_visible_mb

from sys.dm_os_sys_info

go

-- Get me physical RAM installed

-- and size of user VAS

select physical_memory_in_bytes/(1024*1024) as phys_mem_mb,

virtual_memory_in_bytes/(1024*1024) as user_virtual_address_space_size

from sys.dm_os_sys_info

go

--

-- Get me other information about system memory

--

select total_physical_memory_kb/(1024) as phys_mem_mb,

available_physical_memory_kb/(1024) as avail_phys_mem_mb,

system_cache_kb/(1024) as sys_cache_mb,

(kernel_paged_pool_kb+kernel_nonpaged_pool_kb)/(1024) as kernel_pool_mb,

total_page_file_kb/(1024) as total_virtual_memory_mb,

available_page_file_kb/(1024) as available_virtual_memory_mb,

system_memory_state_desc

from sys.dm_os_sys_memory

go

-- Get me memory information about SQLSERVR.EXE process

-- GetMemoryProcessInfo() API used for this

-- physical_memory_in_use_kb

select physical_memory_in_use_kb/(1024) as sql_physmem_inuse_mb,

locked_page_allocations_kb/(1024) as awe_memory_mb,

total_virtual_address_space_kb/(1024) as max_vas_mb,

virtual_address_space_committed_kb/(1024) as sql_committed_mb,

memory_utilization_percentage as working_set_percentage,

virtual_address_space_available_kb/(1024) as vas_available_mb,

process_physical_memory_low as is_there_external_pressure,

process_virtual_memory_low as is_there_vas_pressure

from sys.dm_os_process_memory

go

select * from sys.dm_os_ring_buffers

where ring_buffer_type like 'RING_BUFFER_RESOURCE%'

go

select memory_node_id as node, virtual_address_space_reserved_kb/(1024) as VAS_reserved_mb,

virtual_address_space_committed_kb/(1024) as virtual_committed_mb,

locked_page_allocations_kb/(1024) as locked_pages_mb,

single_pages_kb/(1024) as single_pages_mb,

multi_pages_kb/(1024) as multi_pages_mb,

shared_memory_committed_kb/(1024) as shared_memory_mb

from sys.dm_os_memory_nodes

where memory_node_id != 64

go

with vasummary(Size,reserved,free) as ( select size = vadump.size,

reserved = SUM(case(convert(int, vadump.base) ^ 0) when 0 then 0 else 1 end),

free = SUM(case(convert(int, vadump.base) ^ 0x0) when 0 then 1 else 0 end)

from

(select CONVERT(varbinary, sum(region_size_in_bytes)) as size,

region_allocation_base_address as base

from sys.dm_os_virtual_address_dump

where region_allocation_base_address <> 0x0

group by region_allocation_base_address

UNION(

select CONVERT(varbinary, region_size_in_bytes),

region_allocation_base_address

from sys.dm_os_virtual_address_dump

where region_allocation_base_address = 0x0)

)

as vadump

group by size)

select * from vasummary

go

-- Get me all clerks that take some memory

--

select * from sys.dm_os_memory_clerks

where (single_pages_kb > 0) or (multi_pages_kb > 0)

or (virtual_memory_committed_kb > 0)

go

-- Get me stolen pages

--

select (SUM(single_pages_kb)*1024)/8192 as total_stolen_pages

from sys.dm_os_memory_clerks

go

-- Breakdown clerks with stolen pages

select type, name, sum((single_pages_kb*1024)/8192) as stolen_pages

from sys.dm_os_memory_clerks

where single_pages_kb > 0

group by type, name

order by stolen_pages desc

go

-- Get me the total amount of memory consumed by multi_page consumers

--

select SUM(multi_pages_kb)/1024 as total_multi_pages_mb

from sys.dm_os_memory_clerks

go

-- What about multi_page consumers

--

select type, name, sum(multi_pages_kb)/1024 as multi_pages_mb

from sys.dm_os_memory_clerks

where multi_pages_kb > 0

group by type, name

order by multi_pages_mb desc

go

-- Let's now get the total consumption of virtual allocator

--

select SUM(virtual_memory_committed_kb)/1024 as total_virtual_mem_mb

from sys.dm_os_memory_clerks

go

-- Breakdown the clerks who use virtual allocator

--

select type, name, sum(virtual_memory_committed_kb)/1024 as virtual_mem_mb

from sys.dm_os_memory_clerks

where virtual_memory_committed_kb > 0

group by type, name

order by virtual_mem_mb desc

go

-- Is anyone using AWE allocator?

--

select SUM(awe_allocated_kb)/1024 as total_awe_allocated_mb

from sys.dm_os_memory_clerks

go

-- Who is the AWE user?

--

select type, name, sum(awe_allocated_kb)/1024 as awe_allocated_mb

from sys.dm_os_memory_clerks

where awe_allocated_kb > 0

group by type, name

order by awe_allocated_mb desc

go

-- What is the total memory used by the clerks?

--

select (sum(multi_pages_kb)+

SUM(virtual_memory_committed_kb)+

SUM(awe_allocated_kb))/1024

from sys.dm_os_memory_clerks

go

--

-- Does this sync up with what the node thinks?

--

select SUM(virtual_address_space_committed_kb)/1024 as total_node_virtual_memory_mb,

SUM(locked_page_allocations_kb)/1024 as total_awe_memory_mb,

SUM(single_pages_kb)/1024 as total_single_pages_mb,

SUM(multi_pages_kb)/1024 as total_multi_pages_mb

from sys.dm_os_memory_nodes

where memory_node_id != 64

go

--

-- Total memory used by SQL Server through SQLOS memory nodes

-- including DAC node

-- What takes up the rest of the space?

select (SUM(virtual_address_space_committed_kb)+

SUM(locked_page_allocations_kb)+

SUM(multi_pages_kb))/1024 as total_sql_memusage_mb

from sys.dm_os_memory_nodes

go

--

-- Who are the biggest cache stores?

select name, type, (SUM(single_pages_kb)+SUM(multi_pages_kb))/1024

as cache_size_mb

from sys.dm_os_memory_cache_counters

where type like 'CACHESTORE%'

group by name, type

order by cache_size_mb desc

go

--

-- Who are the biggest user stores?

select name, type, (SUM(single_pages_kb)+SUM(multi_pages_kb))/1024

as cache_size_mb

from sys.dm_os_memory_cache_counters

where type like 'USERSTORE%'

group by name, type

order by cache_size_mb desc

go

--

-- Who are the biggest object stores?

select name, type, (SUM(single_pages_kb)+SUM(multi_pages_kb))/1024

as cache_size_mb

from sys.dm_os_memory_clerks

where type like 'OBJECTSTORE%'

group by name, type

order by cache_size_mb desc

go

select mc.type, mo.type from sys.dm_os_memory_clerks mc

join sys.dm_os_memory_objects mo

on mc.page_allocator_address = mo.page_allocator_address

group by mc.type, mo.type

order by mc.type, mo.type

go