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May 2010
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2010.05.10 15:51 "Re: Increasing the number of files loadable through libtiff", by Bob Friesenhahn
On Mon, 10 May 2010, Simon R. Proud wrote: > > Out of interest: Is there any reason why memory mapping is enabled > by default? Enabling it causes problems like the ones I have been > having and, at least in my case, offers no speed advantage. Libtiff seems to do a lot of file seeking and small reads because of the TIFF directory structures and organization. The memory mapping tends to help hide this because it provides a caching effect. It also helps quite a lot if the input file is opened and read several times without any other intermediate memory-hogging process which might lose the already cached data. Regardless, my own application defaults to not using memory mapping for input files. Bob -- Bob Friesenhahn bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/