4 ms·
What are the difficulties in using some sort of compression algorithm like LZJB on the disk's page file? If, as you say, data can be that easily compressible,
by cninja 16y ago
What are the difficulties in using some sort of compression algorithm like LZJB on the disk's page file?
If, as you say, data can be that easily compressible, the IO speedups from reading the compressed data from disk and space savings would outweigh the CPU cycles necessary to do the decode, but my brief Google search for compressed page file implementations came up with nothing.
- antirez 16y agoA linked list is hard to compress in memory as the overhead is the metadata: pointers, malloc overhead, ... but when written on disk can be represented as prefixed length strings. With VM the live representation and serialization format are the same.
- signa11 16y agojust curious: is it not possible to have some form of unrolled-linked-list to mitigate this effects somewhat ? or perhaps you have already tried it, and it doesn't really fit the bill.
- wrs 16y agoPaul Wilson worked on compressed paging at the turn of the century [1] and tried to address this by introducing specialized compression algorithms for different kinds of pages (e.g., x86 instructions, pointer-filled data structures). Interesting stuff, but I don't think I've ever seen it commercialized, except in Newton OS where we used compressed code pages in binaries (read-only, not swap). [1] http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.26.7895 http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.26.7...
- nitrogen 16y agoHere's something from Android: http://code.google.com/p/compcache/ http://code.google.com/p/compcache/