On Wednesday 30 Jul 2003 17:34, Niklas Bergh wrote: > > > > But I must admit that single-file zipping would be a nicer way to do > > > > it. > > > > I am more in favour of tar.bz2 format. It would be measurably more > > compact for compressible data, with little speed penalty to speak of. > > As a windows user I am not too fond of that idea though....
A couple of things. Firstly, the tar/bzip2 tools are readily available for Windows, and if they are not, the functionality could be added to authoring tools, as the libraries are readily available. Secondly, for single-file compression (completely separate from archive issue), you never need to worry about it. If each file is compressed individually, then that lives at a lower level than archives. Here is what I propose. ZIP archives to be replaced with tar archives. Then, on a lower, "node" level, at insert time, the file being inserted is checked. If it's mime type or extension are indicative of compressed content, we simply insert the file as is. We do the same if the node is explicitly told not to compress the file, e.g. via a flag. If the file still appears to be compressible after that (e.g. html, text, tar), bzip2 compression is applied to the file. The file is compressed and the pre/post compression size is checked. All files in Freenet are padded to the next power of 2 limit, so if the file after compression remains in the same size bracked (padded to the same power of 2 size), there is no point in compressing it. We just throw away the compressed file and insert it uncompressed. This means that compression/decompression overhead is avoided where no space/bandwidth would be saved due to other design issues. Best of all worlds, I think. However, there is something else I have been thinking about. Tar and bzip2 would require extra Java libraries. They exist, but they would have to be bundled with Freenet. This would increase the download size, which is not desirable. ZIP handling is already built in, and would require no additional libraries. The downside is that it generally doesn't seem to compress as well as bz2, and sometimes the difference is quite noticable. Thoughts please. :-) Gordan _______________________________________________ devl mailing list [EMAIL PROTECTED] http://hawk.freenetproject.org:8080/cgi-bin/mailman/listinfo/devl
