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Search Results for: disk write

Percona Live Slides and Video Available: The Right Read Optimization is Actually Write Optimization

In April, I got to give a talk at Percona Live, about why The Right Read Optimization is Actually Write Optimization. It was my first industry talk, so I was delighted when someone in the …

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A Case for Write Optimizations in MySQL

As a storage engine developer, I am excited for MySQL 5.6. Looking at http://dev.mysql.com/tech-resources/articles/whats-new-in-mysql-5.6.html, there has been plenty of work done to improve the performance of reads in MySQL for all storage engines (provided they …

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MLC SSD card lifetime and write amplification

As MLC-based SSD cards are raising popularity, there is also a raising concern how long it can survive. As we know, a MLC NAND module can handle 5,000-10,000 erasing cycles, after which it gets unusable. …

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Write Optimization: Myths, Comparison, Clarifications, Part 2

In my last post, we talked about the read/write tradeoff of indexing data structures, and some ways that people augment B-trees in order to get better write performance. We also talked about the significant drawbacks …

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Write Optimization: Myths, Comparison, Clarifications

Some indexing structures are write optimized in that they are better than B-trees at ingesting data. Other indexing structures are read optimized in that they are better than B-trees at query time. Even within B-trees, …

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Intel 320 SSD random write performance

While I like performance provided by PCI-E cards like FusionIO or Virident tachIOn, I am often asked about SATA drives alternatives, as price of PCI-E cards often is barrier, especially for startups. There is wide …

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Aligning IO on a hard disk RAID – the Benchmarks

In the first part of this article I have showed how I align IO, now I want to share results of the benchmark that I have been running to see how much benefit can we …

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Aligning IO on a hard disk RAID – the Theory

Now that flash storage is becoming more popular, IO alignment question keeps popping up more often than it used to when all we had were rotating hard disk drives. I think the reason is very …

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InnoDB Flushing: a lot of memory and slow disk

You may have seen in the last couple of weekly news posts that Baron mentioned we are working on a new adaptive flushing algorithm in InnoDB. In fact, we already have three such algorithms in …

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Why “insert … on duplicate key update” May Be Slow, by Incurring Disk Seeks

In my post on June 18th, I explained why the semantics of normal ad-hoc insertions with a primary key are expensive because they require disk seeks on large data sets. I previously explained why it …

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