2015.01.01 20:24 "Re: [Tiff] Fast TIFF Reading on Windows", by Aaron Boxer

2015.01.01 17:12 "Re: [Tiff] Fast TIFF Reading on Windows", by Bob Friesenhahn

On Thu, 1 Jan 2015, Aaron Boxer wrote:

> Can anyone recommend the very fastest way of reading TIFF files on windows?

example, there are several ways of reading in the file, including mapping. Has anyone benchmarked performance on memory

> versions of windows? recent

You should be more specific. A common benchmark method is to read the same file repeatedly. I suspect that you are more interested in first-read performance of a large series of images which in total are far larger than system memory. These situations are completely different.

NTFS blocksize can be a factor and the blocksize is specified when the filesystem is created. The blocksize is important since blocksize amount of data will be read (perhaps wastefully) if any byte in the block is accessed. Likewise, larger blocks may result in less apparent fragmentation with large files. The NTFS blocks are still stored accross 512 byte or 4k byte disk sectors.

Windows does not seem to cache filesystem data as agressively as some other systems, which can be both a hinderance and a benefit.

Memory mapped file reads under Windows seem rather similar to Linux.

Bob
--
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/