SQL Server内存性能监视工具

内存压力使查询变慢 (Memory pressure slowing down queries)

This article is the sequel in a series about SQL Server monitoring tools and common performance issues. The first article SQL Server monitoring tools for disk I/O performance is about how to detect and solve high input/output on hard disk subsystems when doing too much work during peak or maintenance times.

本文是有关SQL Server监视工具和常见性能问题的系列文章的续篇。 有关提高磁盘I / O性能SQL Server监视工具的第一篇文章是有关在高峰或维护时间内进行过多工作时如何检测和解决硬盘子系统上大量输入/输出的问题。

This article can be read independently but to get the full picture it’s recommended that part one is read first. Also, because issues described with the disk I/O performance can be manifested from memory issues. Therefore, feel free to check out initial write-up at the following link: SQL Server monitoring tools for disk I/O performance

可以独立阅读本文，但要全面了解，建议您首先阅读第一部分。 同样，因为磁盘I / O性能描述的问题可以从内存问题中看出来。 因此，请随时通过以下链接检查初始记录： 用于磁盘I / O性能SQL Server监视工具

One of the obvious problems with memory that doesn’t really require any SQL Server monitoring tool to be detected is when the system simply doesn’t have enough random-access memory AKA RAM. In such cases, memory pressure can occur because SQL Server simply cannot allocate enough memory.

内存中并不需要任何SQL Server监视工具的明显问题之一就是系统根本没有足够的随机存取内存AKA RAM。 在这种情况下，可能会出现内存压力，因为SQL Server根本无法分配足够的内存。

Hopefully, this will be a short article rather than a long one like I did with disk I/O performance but this stuff is essential to get the complete picture and take all things into account when troubleshooting performace issues. If you’ve troubleshooted memory issue before, then you probably encountered some of the symptoms like system wide performance decrease and I/O increase.

希望这将是一篇简短的文章，而不是像我对磁盘I / O性能所做的那样篇幅较长的文章，但这对于获得完整的概况以及在对性能问题进行故障排除时要考虑到所有因素至关重要。 如果您之前已经解决了内存问题，那么您可能会遇到一些症状，例如系统范围的性能下降和I / O增大。

性能监控工具 (Tools for performance monitoring)

动态管理视图 (Dynamic management views)

So, let’s get started with the Dynamic Management Views AKA DMVs. Most of you knows what DMVs are, but for those who doesn’t, DMVs are views and functions that return server state information which can be used to monitor the health of a server instance, diagnose problems, etc.

因此，让我们开始使用动态管理视图 AKA DMV。 你们中的大多数人都知道DMV是什么，但对于那些不知道的DMV，则DMV是返回服务器状态信息的视图和函数，这些信息可用于监视服务器实例的运行状况，诊断问题等。

The three commonly used DMVs in SQL Server for memory performance are:

SQL Server中用于内存性能的三种常用DMV是：

• sys.dm_os_sys_info sys.dm_os_sys_info
• sys.dm_os_sys_memory