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(mysql.info.gz) Optimize Overview

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 7.1 Optimization Overview
 =========================
 
 The most important factor in making a system fast is its basic design.
 You also need to know what kinds of things your system will be doing,
 and what your bottlenecks are.
 
 The most common system bottlenecks are:
 
    * Disk seeks.  It takes time for the disk to find a piece of data.
      With modern disks, the mean time for this is usually lower than
      10ms, so we can in theory do about 100 seeks a second. This time
      improves slowly with new disks and is very hard to optimize for a
      single table. The way to optimize seek time is to distribute the
      data onto more than one disk.
 
    * Disk reading and writing.  When the disk is at the correct
      position, we need to read the data. With modern disks, one disk
      delivers at least 10-20MB/s throughput. This is easier to optimize
      than seeks because you can read in parallel from multiple disks.
 
    * CPU cycles.  When we have the data in main memory, we need to
      process it to get our result. Having small tables compared to the
      amount of memory is the most common limiting factor. But with
      small tables, speed is usually not the problem.
 
    * Memory bandwidth.  When the CPU needs more data than can fit in
      the CPU cache, main memory bandwidth becomes a bottleneck. This is
      an uncommon bottleneck for most systems, but one to be aware of.
 

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* Design Limitations          MySQL Design Limitations and Tradeoffs
* Portability                 Designing Applications for Portability
* Internal use                What We Have Used MySQL For
* MySQL Benchmarks            The MySQL Benchmark Suite
* Custom Benchmarks           Using Your Own Benchmarks
 
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