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Search Results for: OLTP

Intel 520 SSD in MySQL sysbench oltp benchmark

In my raw IO benchmark of Intel 520 SSD we saw that the drive does not provide uniform throughput and response time, but it is interesting how does it affect workload if it comes from …


OLTP and OLAP – Have Your Cake and Eat it Too!

Looks like we’ll be having some more fun at the Percona Live MySQL Conference! In addition to our booth and my colleague Tim’s talk, my lightning talk was accepted. The title is “OLTP and OLAP …


Update on the InnoDB double-write buffer and EXT4 transactions

In a post, written a few months ago, I found that using EXT4 transactions with the “data=journal” mount option, improves the write performance significantly, by 55%, without putting data at risk. Many people commented on …


MySQL benchmarks on eXFlash DIMMs

In this blog post, we will discuss MySQL performance on eXFlash DIMMs. Earlier we measured the IO performance of these storage devices with sysbench fileio. Environment The benchmarking environment was the same as the one …


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 …


MySQL performance implications of InnoDB isolation modes

Over the past few months I’ve written a couple of posts about dangerous debt of InnoDB Transactional History and about the fact MVCC can be the cause of severe MySQL performance issues. In this post …


How small changes impact complex systems – MySQL example

If you’ve been studying complex systems you know what minor changes might cause consequences of much greater proportions, sometimes causing some effects that are not easily explained at first. I recently ran across a great …


InnoDB crash recovery speed in MySQL 5.6

It has been a while since I have looked at InnoDB crash recovery. A lot has change in the last few years – we have serious crash recovery performance improvements in MySQL 5.5 and MySQL …


Testing TokuDB’s Group Commit Algorithm Improvement

The MySQL 5.6 Release has introduced some changes to how two phase commit works and is managed.  In particular, the commit phase of transactions to the binary log is now serialized and this behavior is …


InnoDB’s multi-versioning handling can be Achilles’ heel

I believe InnoDB storage engine architecture is great for a lot of online workloads, however, there are no silver bullets in technology and all design choices have their trade offs. In this blog post I’m …