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Extreme load and “the operation has been cancelled”
18 September 2011 23:03

There are many reasons why SSAS may generate an operation has been cancelled but i want to take you through a new, although rare, one that i recently discovered. To set the scene I had been tuning the Process Index phase on one of our servers so we could fit a full reindex of a 1.8TB cube comfortably into a maintenance slot over the weekend. I will write another... Read More...

by ACALVETT | with no comments

Filed under: Tips, Performance, Analysis Services, SSAS, 2008, Windows 2003, Processing, SSAS 2008, Operation, Cancelled, W2K3

SSAS 2008 R2 Operations Guide
02 June 2011 14:59

What can i say but WOO HOO! The SSAS 2008 R2 Operations Guide has been published so download your copy now! This document should be considered essential reading and contains over 100 pages of high quality information for configuring, testing and operating an Analysis Services server. Finally i consider this document so important i have made a rare exception and... Read More...

by ACALVETT | 1 comment(s)

Filed under: Tools, Tips, Performance, SSAS 2005, Analysis Services, SSAS, SSAS 2008 R2, 2008 R2, Operations Guide, SSAS 2008, Documentation

Parallelism, CPU Time & DMV’s
30 May 2011 12:04

Whilst reviewing the CPU statistics of a system that i knew was CPU bound i found the numbers were not adding up and i was not seeing the code i expected to see as a top CPU consumer so i decided to going digging. I quickly identified that if the query has gone parallel it: Only shows as one thread in sys.dm_exec_requests because sys. dm_exec_requests does not... Read More...

by ACALVETT | with no comments

Filed under: SQL 2005, Tools, Tips, Performance, Database Engine, 2008, 2008 R2, SQL 2008, CPU, Parallelism, DMV

SSAS Deployment essentials
30 March 2011 00:50

Over the recent years i have enjoyed the privilege of working on a number of different SSAS deployments. Some are huge, some are complex and some of them are huge and complex and most interestingly they all behave differently. What i want to share today is what i consider to be essential for an SSAS installation. This covers what i expect to see installed to... Read More...

by ACALVETT | 2 comment(s)

Filed under: Tools, Tips, Performance, SSAS 2005, Analysis Services, SSAS, 2008, SSAS 2008 R2, 2008 R2

SSAS Native v .net Provider
30 November 2010 19:55

Recently I was investigating why a new server which is in its parallel running phase was taking significantly longer to process the daily data than the server its due to replace. The server has SQL & SSAS installed so the problem was not likely to be in the network transfer as its using shared memory. As i dug around the SQL dmv’s i noticed in sys.dm_exec_connections... Read More...

by ACALVETT | 1 comment(s)

Filed under: Tips, Performance, SSAS 2005, Analysis Services, SSAS

SSAS – Synchronisation performance
08 April 2010 00:15

I’ve always thought of SSAS synchronisation as a clever file mirroring utility built into SSAS and i have never considered the technology as bringing any performance gains to the table. So, its a good job I like to revisit areas…. :) I decided to compare the performance of robocopy and SSAS Synchronisation between 2 Windows 2003 servers running SSAS 2008 SP1... Read More...

by ACALVETT | 2 comment(s)

Filed under: Performance, Analysis Services, SSAS, 2008, Synchronization, Synchronisation

Exploring backup read io performance
24 January 2010 14:12

I was recently exploring how to increase the backup read throughput on one of our SQL servers. Below are some interesting facts i found. I would say that one of the most important reminders that came from the exercise is, do not assume that 2 databases being backup up on the same server using an identical backup command means that the processes are identical... Read More...

by ACALVETT | with no comments

Filed under: SQL 2005, Tips, Performance, Database Engine, 2008, Backup

Enter the SSAS server level lock......
23 November 2009 18:13

Ok, so your reaction to the title is probably the same as mine when i found out about SSAS server level locks! So, i will give you the scripts to reproduce the server level lock but first lets get down to business…. :) Server locks were introduced in one of the SP2 cumulative updates. At the moment i can say it was pre CU12. I`m not sure why it was introduced... Read More...

by ACALVETT | 5 comment(s)

Filed under: Tips, Performance, SSAS 2005, Analysis Services, Hanging, SSAS, Locking

The cost of SSAS metadata management
21 August 2009 06:45

This post will explain how we found ourselves in a situation where when processing a partition the metadata checks took 50 times longer than the actual partition and how to identify what time penalty you are incurring for the metadata checks. The system i was investigating had around 80 cubes with around 100 partitions per cube all hosted in one database and... Read More...

by ACALVETT | 4 comment(s)

Filed under: Tips, Performance, SSAS 2005, Analysis Services

Analysis Server appears to hang…..
05 April 2009 21:40

We had an ongoing problem where by users would suddenly start complaining that the Analysis Server was hanging. When investigating the box we could see that there appeared to be no physical constraints. Disks were a bit above average, CPU was very low and there was plenty of memory. When looking at the server through the SSAS activity viewer (part of the community... Read More...

by ACALVETT | 3 comment(s)

Filed under: Performance, SSAS 2005, Analysis Services, MDX, Hanging