Hello all, We are pleased to announce the first official functional release of Online Hierarchical Storage Manager (OHSM v1.2). This is a RFC release and not yet aimed at mainline inclusion. OHSM is a tool to manage and move data across various class of storage. It can help users to selectively place and move data across tiers such as SSD, Raid 10, Raid 6 based on the attributes of the data. OHSM supports background movement of data without any visible change in a files namespace to users and user applications. OHSM is built as an external module with recompilation required for ext4. The current version of OHSM is based upon kernel 2.6.32.2 This release includes 3 core kernel patches: 1) An initial ext4 patch to adjust ext4's block allocation to use a preferred block range per Ted Tso's Dec 2008 write-up (http://markmail.org/message/qp7zjhhdzxum7rfn). This patch is not ohsm specific. 2) A ohsm specific ext4 patch to provide callouts to the ohsm module. 3) The ohsm module itself The source code for OHSM v1.2 is freely distributable under GPL. The latest stable OHSM v1.2 is available at : http://sourceforge.net/projects/ohsm/files/OHSMv1.2.tar.gz/download Sources are available as git repository at : git://ohsm.git.sourceforge.net/gitroot/ohsm/ohsm The following list describes the features of OHSM * Support for Ext4. * File System callouts * Policy based File Migration * Per inode information maintainer in user xattr area * XML based policy files * Support for RAID * DTD based XML validation - Automatic Relocation engine * Selective Relocation of mountpoint/Subdirectories * Selection Relocation based on specific rule * File Placement based on: + UID + GID + File Type + Directory Name * File Migration based on + UID + GID + FILE SIZE + ACCESS AGE + MODIFICATION AGE - File Access Temperatue - File I/O Temperature + (*=current features, -= on our todo list, +=support already present) Here are some simple examples :- $ ohsm enable sample/ohsm.xml OHSM enabled successfully on '/tmp/mnt' $ ohsm relocate -m /tmp/mnt Relocation performed successfully. $ ohsm status /tmp/mnt OHSM is enabled on '/tmp/mnt' $ ohsm disable /tmp/mnt OHSM disabled successfully on '/tmp/mnt' $ ohsm Usage: ohsm subcommand [optstring ..] [parameters ..] Subcommands : enable - Enable OHSM disable - Disable OHSM status - Show status of OHSM relocate -Trigger relocation on filesystem update - Update OHSM instance parameters help -Show usage *Note* that the code for OHSM is still in early stages Feedback, bug reports and patches, as always, are welcomed. (ohsm-devel@xxxxxxxxxxxxxxxxxxxxx) -- Thanks - OHSM team -- 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
