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Testing the Group Commit Fix

As you may know, Kristian Nielsen made a fix for the Group Commit Problem which we many times wrote about. The fix came into MariaDB 5.3 and Mark Callaghan tested it recently . We ported …

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Shard-Query turbo charges Infobright community edition (ICE)

Shard-Query is an open source tool kit which helps improve the performance of queries against a MySQL database by distributing the work over multiple machines and/or multiple cores. This is similar to the divide and …

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How InnoDB handles REDO logging

Xaprb (Baron) recently blogged about how InnoDB performs a checkpoint , I thought it might be useful to explain another important mechanism that affects both response time and throughput – The transaction log.

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More on dangers of the caches

I wrote couple of weeks ago on dangers of bad cache design. Today I’ve been troubleshooting the production down case which had fair amount of issues related to how cache was used. The deal was …

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FlashCache: more benchmarks

Previously I covered simple case with FlashCache, when data fits into cache partitions, now I am trying to test when data is bigger than cache. But before test setup let me address some concern (which …

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High Insertion Rates into a TokuDB Table with Durable Transactions

We recently made transactions in TokuDB 3.0 durable. We write table changes into a log file so that in the event of a crash, the table changes up to the last checkpoint can be replayed. …

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Why you don’t want to shard.

Note: This blog post is part 1 of 4 on building our training workshop.

The Percona training workshop will not cover sharding. If you follow our blog, you’ll notice we don’t talk much about the subject; in some cases it makes sense, but in many we’ve seen that it causes architectures to be prematurely complicated.

So let me state it: You don’t want to shard.

Optimize everything else first, and then if performance still isn’t good enough, it’s time to take a very bitter medicine. The reason you need to shard basically comes down to one of these two reasons

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Three key things to know about moving MySQL into the cloud.

The question “what problems will I have when migrating to the cloud” gets asked often enough. If by cloud you mean Amazon EC2, then from a technical perspective there isn’t much that changes. The biggest …

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SSD, XFS, LVM, fsync, write cache, barrier and lost transactions

We finally managed to get Intel X25-E SSD drive into our lab. I attached it to our Dell PowerEdge R900. The story making it running is worth separate mentioning – along with Intel X25-E I …

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Pretending to fix broken group commit

The problem with broken group commit was discusses many times, bug report was reported 3.5 years ago and still not fixed in MySQL 5.0/5.1 (and most likely will not be in MySQL 5.1). Although the rough truth is …

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