---
title: "sys.dm_exec_query_resource_semaphores (Transact-SQL) | Microsoft Docs"
ms.custom: ""
ms.date: "08/09/2016"
ms.prod: "sql-non-specified"
ms.reviewer: ""
ms.suite: ""
ms.technology: 
  - "database-engine"
ms.tgt_pltfrm: ""
ms.topic: "language-reference"
f1_keywords: 
  - "sys.dm_exec_query_resource_semaphores_TSQL"
  - "dm_exec_query_resource_semaphores_TSQL"
  - "sys.dm_exec_query_resource_semaphores"
  - "dm_exec_query_resource_semaphores"
dev_langs: 
  - "TSQL"
helpviewer_keywords: 
  - "sys.dm_exec_query_resource_semaphores dynamic management view"
ms.assetid: e43a2aa9-dd52-4c89-911e-1a7d05f7ffbb
caps.latest.revision: 30
author: "JennieHubbard"
ms.author: "jhubbard"
manager: "jhubbard"
---
# sys.dm_exec_query_resource_semaphores (Transact-SQL)
[!INCLUDE[tsql-appliesto-ss2008-all_md](../../includes/tsql-appliesto-ss2008-all-md.md)]

  Returns the information about the current query-resource semaphore status in [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)]. **sys.dm_exec_query_resource_semaphores** provides general query-execution memory status and allows you to determine whether the system can access enough memory. This view complements memory information obtained from [sys.dm_os_memory_clerks](../../relational-databases/system-dynamic-management-views/sys-dm-os-memory-clerks-transact-sql.md) to provide a complete picture of server memory status. **sys.dm_exec_query_resource_semaphores** returns one row for the regular resource semaphore and another row for the small-query resource semaphore. There are two requirements for a small-query semaphore:  
  
-   The memory grant requested should be less than 5 MB  
  
-   The query cost should be less than 3 cost units  
  
> [!NOTE]  
>  To call this from [!INCLUDE[ssSDWfull](../../includes/sssdwfull-md.md)] or [!INCLUDE[ssPDW](../../includes/sspdw-md.md)], use the name **sys.dm_pdw_nodes_exec_query_resource_semaphores**.  
  
|Column name|Data type|Description|  
|-----------------|---------------|-----------------|  
|**resource_semaphore_id**|**smallint**|Nonunique ID of the resource semaphore. 0 for the regular resource semaphore and 1 for the small-query resource semaphore.|  
|**target_memory_kb**|**bigint**|Grant usage target in kilobytes.|  
|**max_target_memory_kb**|**bigint**|Maximum potential target in kilobytes. NULL for the small-query resource semaphore.|  
|**total_memory_kb**|**bigint**|Memory held by the resource semaphore in kilobytes. If the system is under memory pressure or if forced minimum memory is granted frequently, this value can be larger than the **target_memory_kb** or **max_target_memory_kb** values. Total memory is a sum of available and granted memory.|  
|**available_memory_kb**|**bigint**|Memory available for a new grant in kilobytes.|  
|**granted_memory_kb**|**bigint**|Total granted memory in kilobytes.|  
|**used_memory_kb**|**bigint**|Physically used part of granted memory in kilobytes.|  
|**grantee_count**|**int**|Number of active queries that have their grants satisfied.|  
|**waiter_count**|**int**|Number of queries waiting for grants to be satisfied.|  
|**timeout_error_count**|**bigint**|Total number of time-out errors since server startup. NULL for the small-query resource semaphore.|  
|**forced_grant_count**|**bigint**|Total number of forced minimum-memory grants since server startup. NULL for the small-query resource semaphore.|  
|**pool_id**|**int**|ID of the resource pool to which this resource semaphore belongs.|  
|**pdw_node_id**|**int**|**Applies to**: [!INCLUDE[ssSDWfull](../../includes/sssdwfull-md.md)], [!INCLUDE[ssPDW](../../includes/sspdw-md.md)]<br /><br /> The identifier for the node that this distribution is on.|  
  
## Permissions  
 On [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] requires VIEW SERVER STATE permission on the server.  
  
 On [!INCLUDE[ssSDS](../../includes/sssds-md.md)] Premium Tiers requires the VIEW DATABASE STATE permission in the database. On [!INCLUDE[ssSDS](../../includes/sssds-md.md)] Standard and Basic Tiers requires the [!INCLUDE[ssSDS](../../includes/sssds-md.md)] admin account.  
  
## Remarks  
 Queries that use dynamic management views that include ORDER BY or aggregates might increase memory consumption and thus contribute to the problem they are troubleshooting.  
  
 Use **sys.dm_exec_query_resource_semaphores** for troubleshooting but do not include it in applications that will use future versions of [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)].  
  
 The Resource Governor feature enables a database administrator to distribute server resources among resource pools, up to a maximum of 64 pools. In [!INCLUDE[ssSQL11](../../includes/sssql11-md.md)] and higher, each pool behaves like a small independent server instance and requires 2 semaphores.  
  
## See Also  
 [Execution Related Dynamic Management Views and Functions &#40;Transact-SQL&#41;](../../relational-databases/system-dynamic-management-views/execution-related-dynamic-management-views-and-functions-transact-sql.md)   
 [sys.dm_exec_query_memory_grants &#40;Transact-SQL&#41;](../../relational-databases/system-dynamic-management-views/sys-dm-exec-query-memory-grants-transact-sql.md)