** Summary changed: - No support for hybrid hard drive + No support for NV cache on hybrid hard drive
** Description changed: Binary package hint: linux-source-2.6.24 As far as I'm aware, there's no support for the non-volatile RAM cache on hybrid hard drives (SATA disk plus non-volatile RAM) under Ubuntu / Linux. Using the non-volatile RAM could reduce power consumption by increasing time between spin-ups, and reducing the risk of data loss if the heads are parked suddenly during vibration. If boot-up files are put on the flash then booting can be faster and consume less power too. The drive in my laptop is a 160GB Seagate ST91608220AS with 256 MB flash. Until NV cache is supported, hybrid hard drives work as ordinary SATA disks. papers describing NV cache implementations are here: http://www.ssrc.ucsc.edu/Papers/ssrctr-07-04.pdf http://www.soe.ucsc.edu/~darrell/Papers/MASCOTS-Bisson-06.pdf And the specification is in ATA8-ACS: 33 e05106r7 New Feature: Adds commands to manipulate NV cache in hybrid devices http://www.t13.org/Documents/UploadedDocuments/docs2007/D1699r4a- ATA8-ACS.pdf + + There is an open question about the licensing of NV cache technology, + but I received this from Seagate confirming that there are no patent + issues for developing Linux support (at least for Seagate's products). + + ----------------- + Response (Jason H.) 09/05/2008 09:32 + There are no obstructions if you or someone wants to do that. Seagate would not be able to support it, but you can do it. + ------------------ + + ::My query:: + I own an ST91608220AS Momentus hybrid hard drive and run Linux. As far as I am aware, the NV cache of the device is not utilised by Linux. The specification for accessing NV cache is published in ATA8-ACS. + Are there any legal obstructions (licences, patents) to Linux developers wishing to add NV cache support to the kernel? + ------------------- -- No support for NV cache on hybrid hard drive https://bugs.launchpad.net/bugs/178654 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
