>>>>> "Ted" == Ted Ts'o <tytso@xxxxxxx> writes: Ted, Ted> OK, but what do we do when we start seeing devices with 8k or 16k Ted> physical block sizes? The VM doesn't deal well with block sizes > Ted> page size. I don't think we're going to see devices reporting logical blocks bigger than 4KiB anytime soon. Too much pain for everybody in the industry (most other operating systems can't even deal with 4KiB logical blocks yet). Eventually we will have to do the required page cache surgery to support filesystem block sizes bigger than the page size. But I don't think that's something we'll have to deal with in the immediate future. In the meantime, however, the question is whether there is something we can do in the allocators to mitigate effects of devices reporting physical blocks bigger than PAGE_CACHE_SIZE. Obviously this would be in the I/O hint/alignment category and not something which would guarantee that all writes would be aligned multiples of that physical block size. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
