Tagged Questions

0
votes
0answers
42 views

Temporarly disable cache in oracle 11g

I want to disable the caching for my session in oracle 11g to see how long a query takes. Is this possible or is there a better way for meassuring the time a query takes to run?
13
votes
4answers
548 views

Why would I NOT use the SQL Server option “optimize for ad hoc workloads”?

I've been reading some great articles regarding SQL Server plan caching by Kimberly Tripp such as this one: http://www.sqlskills.com/blogs/kimberly/plan-cache-and-optimizing-for-adhoc-workloads/ Why ...
0
votes
1answer
211 views

Qcache_free_memory not full yet I get alot of Qcache_lowmem_prunes

I just started dabbling with query cache for our CMS. Can anyone tell me why (or at least a good guess) I get alot of Qcache_lowmem_prunes when more than half of Qcache_free_memory is free? ...
7
votes
2answers
346 views

PostgreSQL Index Caching

I'm having difficulty finding 'lay' explanations of how indexes are cached in PostgreSQL, so I'd like a reality check on any or all of these assumptions: PostgreSQL indexes, like rows, live on disk ...
7
votes
2answers
787 views

Is the overhead of frequent query cache invalidation ever worth it?

I'm currently working on a MySQL database where we are seeing a large number of invalidations from the query cache, primarily because of the high number of INSERT, DELETE and UPDATE statements that ...
8
votes
3answers
2k views

How to boost performance of virgin queries in MS SQL Server?

I have ASP.NET web site that does it's own independent caching of data and data does not change for long periods of time, so it does not need to query SQL Server second time with same query. I need to ...
4
votes
1answer
575 views

How to calculate cache misses for PostgreSQL

I'm administering a server where a tool using a PostgreSQL runs. The tool takes care of most PostgreSQL configurations by itself, but I'm observing some performance problems. I could confirm at OS ...