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seen Dec 16 at 10:34

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awarded  Nice Question
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awarded  Notable Question
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awarded  Popular Question
Aug
14
comment How do I determine how much data is being written per day through insert, update and delete operations?
An exceptionally well researched answer, thanks very much for your insights.
Aug
14
accepted How do I determine how much data is being written per day through insert, update and delete operations?
Aug
13
revised How do I determine how much data is being written per day through insert, update and delete operations?
Added mysql tag.
Aug
13
revised How do I determine how much data is being written per day through insert, update and delete operations?
Expanded question for clarity.
Aug
13
asked How do I determine how much data is being written per day through insert, update and delete operations?
Sep
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awarded  Scholar
Sep
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accepted Is the overhead of frequent query cache invalidation ever worth it?
Sep
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comment Is the overhead of frequent query cache invalidation ever worth it?
Regarding your comment about "mysql has no internal mechanism for defragmenting the query cache", can't you execute the command FLUSH QUERY CACHE to defragment it? See: dev.mysql.com/doc/refman/5.0/en/flush.html
Sep
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comment Is the overhead of frequent query cache invalidation ever worth it?
Hehe, very insightful.
Sep
6
comment Is the overhead of frequent query cache invalidation ever worth it?
Thanks for the response, I look forward to the rest. One of the things we did identify was that about 18% of queries weren't being cached, so definitely appreciate the advice regarding the settings. Unfortunately the box isn't dedicated, but your recommendations should help. Fragmentation is definitely an issue as well. I'm still really concerned about the number of invalidations we're seeing (as opposed to queries that are not cached at all), so still uncertain whether or not the overhead there is worth it. Really appreciate your insight, thank you very much.
Sep
6
comment Is the overhead of frequent query cache invalidation ever worth it?
Updated with the additional info you requested. Thanks.
Sep
6
revised Is the overhead of frequent query cache invalidation ever worth it?
Added additional info requested by user.
Sep
5
awarded  Editor
Sep
5
comment Is the overhead of frequent query cache invalidation ever worth it?
Updated with info as requested. Thanks!
Sep
5
revised Is the overhead of frequent query cache invalidation ever worth it?
Updated based on user's question.
Sep
5
comment Is the overhead of frequent query cache invalidation ever worth it?
Thanks for the response. I have that book and have been using it extensively; am well aware of the reasons you outline for cache misses, but as I mentioned, we have already identified cache invalidations as being a key issue due to the strong correlation we're seeing between Com_select and Qcache_inserts. Oh, and the DB in question has a mix of INNODB and MyISAM.
Sep
5
awarded  Student