http://bugs.openzim.org/show_bug.cgi?id=9
Summary: optimize cluster size (small devices limitations) Product: openZIM Version: unspecified Platform: All OS/Version: All Status: NEW Severity: enhancement Priority: P5 Component: zimwriter AssignedTo: tommi@tntnet.org ReportedBy: manuel.schneider@wikimedia.ch CC: dev-l@openzim.org Estimated Hours: 0.0
Small devices don't have much memory. Through built-in article clustering ZIM optimizes the compression ratio of the article texts.
Currently the cluster size can be determined at ZIM-build-time by the ZIM-creator.
We must do some research to find out which cluster size is at maximum possible so the reader still works on a small device and communicate the requirements - such as "8 MB at least". This cluster size should then be the default at zimwriter.
If we not do so it can happen that a ZIM-creator chooses as cluster size which does not work on small devices, so these files can not be read there.
http://bugs.openzim.org/show_bug.cgi?id=9
Tommi Mäkitalo tommi@tntnet.org changed:
What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED Resolution| |WONTFIX
--- Comment #1 from Tommi Mäkitalo tommi@tntnet.org 2009-11-07 21:32:30 CET --- Bug #10 should resolve that. It is not reasonable to create device specific zim files. Instead Bug #10 makes the number of clusters, which are cached when reading configurable. When the default cluster size of 1MB is used, and the cache size is set to 0, this 1MB is needed, which I feel is a reasonable value. I don't think we need to support devices, which have less memory.
1MB is also the value, which is normally used in compression libraries. So it increasing the value does not lead to better compression ratios. On the other side smaller values lead to worse compression ratios.