Monday Mar 17, 2008

SAM-QFS Code Open Sourced

We are please to announce that we have open sourced the SAM-QFS code! This major contribution to the OpenSolaris community is available on We are very excited to take this big step in creating an open source community around SAM-QFS and continuing to grow Open Solaris as a premier storage OS.

So, I'd like to explain where we are today and where we are going relative to posting the source. Getting all of the Sun SAM-QFS IP posted for Community viewing and download was priority number one. This announcement is about that first milestone. We are looking forward to connecting with developers, early adopters, and users through our open source effort. Eventually we plan to externalize the source via Mercurial to facilitate community code contributions.

What we are delivering is our current development source. Our goal is to have the community be part of the development process, so we are intentionally posting our development work instead of released software, such as the SAM-QFS 4.6 code. By delivering development source, the community can influence and contribute to development of future releases, and it allows early adopters to quickly get access to the latest features. This change should benefit not only the future SAM-QFS releases and therefore customers. In addition, it will benefit those that would like to adopt or experiment with Solaris as a storage platform.

This initial post is a gzipp'd tarball of our latest development build. Some third party components were removed for legal reasons. Therefore, this first posting won't build unless the missing third party components are added back or coded around. This is a temporary solution until we either get legal permission to post the third party source or recode those sections so that they can be built with or without the third party components.

We look forward to feedback about what we have posted and what you as the SAM-QFS community would like to see in future source code uploads. To that end, we have two discussion lists for communication.

1) SAM-QFS-DISCUSS - The discussion list for general topics or issues

2) SAM-QFS-DEV - The development alias for specific questions about source, source contributions, or code reviews

Again, please join us at the OpenSolaris SAM-QFS project page ( We look forward to your comments and involvement.

'til next time, Ted

Thursday Mar 06, 2008

Development update: Archiver

We are actively working on the archiver to improve SAM scalability and performance. One area we are focusing on is reducing the scanning and therefore metadata footprint of the archiver. Currently, the noscan method of the archiver gathers inode (file) events to determine whether and when an inode needs to be archived. After receiving the event, the archiver schedules a scan of the associated directory. The list of directories to be scanned become the archiver's worklist. We are working to improve archiver performance by changing the sam-arfind daemon's worklist from a list of directories requiring scanning (in order to find files requiring examination), to the actual list of file inodes requiring examination.

Keeping the actual list of inodes should significantly reduce the frequency scans done by the archiver. In general, most inode events would require examination within minutes or hours. However, for those longer time frame examinations, only those files that need to be examined within a "rolling window" of time are kept in the worklist. The duration of the "rolling window" is specified by the 'background_interval' in the archiver.cmd file. The default might be 24 hours. Files that require examination after this time will be found during the next background scan. The time of day for the background scan is specified by the 'background_time' in the archiver.cmd file. The default might be (midnight). The intent of these tunables is to allow the administrator to schedule the background scans at a frequency and time that minimizes archiver scan impact to production.

'til next time, Ted

Wednesday Mar 05, 2008

New 4.5 and 4.6 patches released

The 4.6-04 patch and the 4.5-06 patch are now available for download. In addition to the usual bug fixes, we added quite a bit of new support in the 4.6-04 patch.

Newly Qualified with SAM-QFS 4.6-04

1) The Sun StorageTek 5800 System Version 1.1 is supported with SAM-QFS.

2) The HP LTO4 tape drive is now qualified with SAM.

3) ACSLS 7.2 is now qualified with SAM-QFS.

4) The Sony Super AIT2 tape drive is now qualified with SAM-QFS.

5) The HP SL48 library is now qualified with SAM-QFS

6) The Sun VTL and the following drives are now qualified with SAM-QFS: HP LTO3 IBM LTO3 STK 9940C STK 9840B STK T10K

7) Intel EM64T 64 bit architecture servers are supported with SAM-QFS, including SAM and Shared QFS MDS on Solaris 10 and Shared QFS clients on Solaris 10, Red Hat 4, and SLES 10 OSs.

Here is the link to the wiki:


    'til next time, Ted

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    Ted Pogue


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