Andi Kleen <andi@xxxxxxxxxxxxxx> wrote: > > If you have only 256 MB of RAM, I'm afraid the machine dives into swap > > the moment it attempts to process that single 150-MB object during > > repacking. Objects are always allocated entirely, including the > > deflated and inflated copy at some point. Making git handle partial > > objects in memory would add complexity all over the map so I don't think > > it'll ever be implemented nor be desirable. > > If the access pattern is sequential and not much reuse it might be possible > to madvise() strategically to do prefetch and early unmap of not used > anymore data. I used that successfully in a few programs in the past that did > aggressive mmap on very large files. We actually do something better where we can. However parts of Git assume that it can get back a contiguous block of memory which contains the entire file content, decompressed. The data is stored on disk compressed, so we cannot just mmap the data from disk. -- Shawn. -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
