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Search Results for: profiler

Three ways that the poor man’s profiler can hurt MySQL

Over the last few years, Domas’s technique of using GDB as a profiler has become a key tool in helping us analyze MySQL when customers are having trouble. We have our own implementation of it …

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Looking deeper into InnoDB’s problem with many row versions

A few days ago I wrote about MySQL performance implications of InnoDB isolation modes and I touched briefly upon the bizarre performance regression I found with InnoDB handling a large amount of versions for a single …

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How expensive is USER_STATISTICS?

One of our customers asked me whether it’s safe to enable the so-called USER_STATISTICS features of Percona Server in a heavy-use production server with many tens of thousands of tables. If you’re not familiar with …

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Binary log file size matters (sometimes)

I used to think one should never look at max_binlog_size, however last year I had a couple of interesting cases which showed that sometimes it may be very important variable to tune properly. I meant …

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Percona Live Keynote Speaker: Mark Callaghan

Mark Callaghan has graciously accepted to be the closing keynote speaker for Percona Live: San Francisco! Mark is best known for his work behind MySQL @ Facebook, where he and his team maintain one of …

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Stripped MySQL builds, the optimization that isn’t

I usually tell people to use official MySQL builds from MySQL, or from their operating system distribution if they don’t want to do that. (This assumes that there is no compelling reason to use third-party …

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To find the bottleneck, stop guessing and start measuring

We recently examined a customer’s system to try to speed up an ETL (Extraction, Transformation and Loading) process for a big data set into a sort of datamart or DW.  What we typically do is …

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