track.performance

Performance tuning with track involves trading off memory use for
  faster access times to objects.  Access time is fastest when all
  objects are cached in memory, but memory can be exhausted if this is
  done.  Memory use is minimized when objects are not cached in memory
  at all, but then a file must be read or written each time an object is
  referenced, and the whole file must be read or written even if only a
  small part of the object is actually used or changed.

  The default mode of operation of track balances memory use and
  access times by keeping objects in memory for the duration of a
  top-level task, and flushing them out at the end of the task.

  Three options (see <a href="/link/track.options?package=track&version=1.0-13" rd-options="" data-mini-rdoc="track::track.options">track.options</a>) control performance:
  <ul><li>cache</li></ul>: <code>TRUE</code>/<code>FALSE</code> should variables be cached at all?
    <item>cachePolicy</item>: <code>tltPurge</code>/<code>none</code> higher level
    policy for maintaining cache
    <item>writeToDisk</item>: <code>TRUE</code>/<code>FALSE</code> should objects be
    written after a change?

data

Automatically stores objects in files on disk
  so that files are rewritten when objects are changed, and
  so that objects are accessible but do not occupy memory
  until they are accessed. Keeps track of times when objects
  are created and modified, and caches some basic
  characteristics of objects to allow for fast summaries of
  objects.  Also provides a command history mechanism that
  saves the last command to a history file after each
  command completes.

Tony Plate

track

Track Objects

track.performance function

<ul><li>cache=TRUE, cachePolicy="tltPurge", writeToDisk=TRUE</li></ul>

itemize

<ul><li>cache=TRUE, cachePolicy="none", writeToDisk=TRUE</li><li>cache=TRUE, cachePolicy="none", writeToDisk=FALSE</li><li>cache=FALSE, cachePolicy="none", writeToDisk=TRUE</li></ul>

track.performance: Performance tuning with track.

Description

Arguments

itemize

item

code

See Also