>>>>> "Andreas" == Andreas Dilger <adilger@xxxxxxxxx> writes: Andreas, Andreas> What are your thoughts on reserving a small number of the Andreas> stream ID values for filesystem metadata (e.g. the first 31 Andreas> since 0 == unused)? The stream ID address space might be 16-bit but the devices currently being discussed can only handle a few concurrently open streams (4, 8, 16). Discussions are ongoing about whether the devices should be able to implicitly close a stream based on LRU or something similar when the hw max is reached. But as it stands you have to explicitly close an existing stream with a separate command when the max is reached. Otherwise a write with a previously unused stream ID will fail. I.e. there is a significant cost to switching between stream IDs and thus I am afraid the current stuff isn't well suited to having a fine grained tagging approach like the one you are proposing. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
