[lm-announce] IMPORTANT: LMF file server upgrades

[Jonathan Buzzard]

We are planing a major upgrade of the Light Microscope file system over the Christmas period.

In line with current best practice we plan to move all the metadata on to dedicated fast disks. This should help performance. For reference metadata is all the information about files, such as what directory it is in, who it belongs to, where on the physical disks it is stored etc.

The first stage is to add a whole bunch of new disk to the storage systems, and upgrade the to the latest version of GPFS. This is scheduled for the 07:00-09:00 maintenance window on Tuesday the 15th December. During this time the LMF will be unavailable.

The second stage is to shuffle all the data on the disks about so all the metadata is moved onto the new dedicated fast disks. This will commence at 17:00 on Wednesday the 23rd of December. Access to the LMF will be maintained throughout this reoganization.

This second stage is a long running operation that we anticipate will take some days to complete. While it is in progress the performance of the LMF will be significantly degraded as 70,000GB of data on disk is shuffled about.

While we anticipate that the reorganization will have completed by Tuesday the 5th of January, we cannot guarantee this. I will however be logging in daily during the Christmas period to keep any eye on the reorganization in case of problems.

We thank you for your patience and look forward to an improved LMF in 2010.


JAB.



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Jonathan A. Buzzard                      Tel: +441382-386998
Storage Administrator, College of Life Sciences
University of Dundee, DD1 5EH

The University of Dundee is a registered Scottish charity, No: SC015096