Hi Park, Thanks a lot for the response. >It seems similar with TRIM. So how about to consider TRIM >implementation or extend it? Yes, file system set REQ_DISCARD flag to notify block device driver to execute TRIM. And I noticed there's already a flag REQ_META used for file system meta data. But seems only gfs2 file system uses the REQ_META flag, other file systems (including ext4 and btrfs) have not used this flag. Is the flag useless or any other reason? >I'm not familiar with NCQ implementation but it's also helpful to implement it. I don't know much about NCQ, too. Just have a impression that NCQ is only for SATA hard disk, can it also be used for block device, such as the mmc block device? Thanks. Regards, Yunpeng -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
