I'm running 3.11 kernel, and I've been playing around with bcache. I'd like to set something up where I can spin down the hard disks to save power, reading and writing to the SSD as much as possible. It is working quite well performance wise, with normal sequential speed as well as greatly improved random access speeds. To avoid spinning up the disk for writes, I have enabled writeback mode. I would like to increase writeback_delay, but whatever I set it to has no effect. If I spin down the hard disk with 'hdparm -Y /dev/sda', touch a file on the mounted share, exactly 30 seconds after I touch the file (the default writeback_delay) the hard drive spins up, regardless of what I echo to writeback_delay, even though a cat of writeback_delay shows it has changed. Any ideas? Do I need to set writeback_delay in some sequence for it to take effect? Thanks, Ryan -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
