Priority Queuing In Azure SQL Data Warehouse

Matt How walks us through an improvement to Azure SQL Data Warehouse:

The concept of workload management is a key factor for Azure SQL DW as there is only limited concurrency slots available and depending on the resource class, these slots can fill up pretty quickly. Once the concurrency slots are full, queries are queued until a sufficiently sized slot is opened up. Let’s recap what Resource Classes are and how they affect workload management.

A Resource Class is a pre-configured database role that determines how much resource is allocated to queries coming from users that belong to that role. For example, an ETL service account may use a “large” resource class and be allocated a generous amount of the server, however an analyst may use a “small” resource class and therefore only use up a small amount of the server with their queries. There are actually 2 types of resource class, Dynamic and Static. The Dynamic resource classes will grant a set percentage of memory to a query and actual value of this percentage will vary as the Warehouse scales up and down. The key factor is that an xLargeRc (extra-large resource class) will always take up 70% of the Server and will not allow any other queries to be run concurrently. No matter how much you scale up the Warehouse, queries run with an xLargeRc will run one at a time. Conversely, queries run with a smallrc will only be allocated 4% of the Server and therefore as a Warehouse scales up, this 4% becomes a larger amount of resource and can therefore process data quicker.

This looks like a useful addition.  Click through for a few examples of how it will work.

Related Posts

Azure Dedicated Hosts in Preview

Mine Tokus covers the benefit of Azure Dedicated Hosts: Recently introduced, Azure Dedicated Host Preview provides single-tenant physical servers that can host one or more virtual machines. With this new hosting model, physical server is dedicated to your organization and capacity isn’t shared with other customers. Physical server-level isolation helps to address security and compliance requirements, brings visibility […]

Read More

Connecting to Redshift from Azure Analysis Services

Gilbert Quevauvilliers shows how we can connect to Amazon Redshift from Azure Analysis Services: I am busy working with a customer and had a challenge when using Azure Analysis Services to connect to Amazon Redshift via an ODBC connection. The first issue that I encountered was the following error: OLE DB or ODBC error: [Microsoft][ODBC […]

Read More

Categories

November 2018
MTWTFSS
« Oct Dec »
 1234
567891011
12131415161718
19202122232425
2627282930