How to ignore query parameters in web cache

cachehttp

Google Analytics use some query parameters to identify campaigns and to do cookie control. This is all handled by javascript code. Take a look at the following example:

http://www.example.com/?utm_source=newsletter&utm_medium=email&utm_ter m=October%2B2008&utm_campaign=promotion

This will set cookies via JavaScript with the right campaign origin. This query parameters can have multiple and sometimes random values. Since they are used as cache hash keys the cache performance is heavily degraded in some scenarios.

I suppose there's a not so hard configuration on cache servers to just ignore all query parameters or specific query parameters. Am I right?

Does anyone know how hard is it in popular web cache solutions, to create ?

I'm not interested in a specific web cache solution. It would be great to hear about the one you use.

Best Answer

Fiddling with the cache is not the right way to go about this.

The "right" way to handle URLs with this sort of tracking is to send a 301 redirect to your canonical URL (after actually doing any necessary tracking, of course).

Related Solutions

Sql-server – How to remove a specific bad plan from the SQL Server query cache

I figured out a few things

select * from sys.dm_exec_query_stats

will show all the cached query plans. Unfortunately, no SQL text is shown there.

However, you can join the SQL text to the plans like so:

select plan_handle, creation_time, last_execution_time, execution_count, qt.text
FROM 
   sys.dm_exec_query_stats qs
   CROSS APPLY sys.dm_exec_sql_text (qs.[sql_handle]) AS qt

From here it's pretty trivial to add a WHERE clause to find the SQL I know is in the query, and then I can execute:

DBCC FREEPROCCACHE (plan_handle_id_goes_here)

to remove each query plan from the query plan cache. Not exactly easy or convenient, but it appears to work..

edit: dumping the entire query cache will also work, and is less dangerous than it sounds, at least in my experience:

DBCC FREESYSTEMCACHE ('ALL') WITH MARK_IN_USE_FOR_REMOVAL;

Postgresql – Reset Postgres query cache

There was a post on serverfault a while ago that covered this topic.

Check this out...

https://stackoverflow.com/questions/1216660/see-and-clear-postgres-caches-buffers

I hope that helps.

David

Best Answer

Related Solutions

Sql-server – How to remove a specific bad plan from the SQL Server query cache

Postgresql – Reset Postgres query cache

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