08/30/05gdm project presentation lower storage summary of activity on 8/30/2005

08/30/05 GDM Project Presentation

Lower Storage

Summary of activity on 8/30/2005


Project Drivers & Scope

Drivers - DRAFT V0.13 12/14/04 [1] Lower Storage

ENCP

44/8/51 2 12 4 16/8 1 2 2 2 3

COMMON X

COMMON X

COMMON Common Job Submission and Management servicesCOMMON Distributed, diversely located, persistent data store X X

COMMON X X X X

D0 Continued Stable Operation ongoing X X X X X XD0 Tape migration support 12/01/05 X XD0 More Efficient Tape Drive Usage XCDF Tape migration support X XCMS DC07 CMS 50% Data Challenge 03/01/07 ? ?Theory Lattice Gauge Facility

MINOS Robust & Stable Operation X X

Top Level Activities

Character in Cells: X = development, I = integration, L = low

priority, H = high priority, ? = ?

Priority& Date of

next Milestone

Lower Storage

[1]

DAY TO DAY

OPERATION

SUPPORT

SMALL PROJECT

S

DISTRIBUTED TAPE

OPERATION

FTT SUPPORT

OPEN SCIENCE

GRID DATA

Next Generatio

n Tape

SECOND GENERA

TION MONITO

RING

TAPE MIGRATIO

N SUPPORT

FTE months in FY05 Available/ Posted/ Needed/Outsourced: Increase our effective use of resources across our

stakeholdersCommon and/or interoperable Services with OSG and LCG

Distributed permanent & custodial data storage not only at FCC

High Priority


Project Milestones• High Priority

– Day to day support, has no specific requirements• Ongoing

– day to day support• Migration of CMS tapes. Direct and reverse pnfs scans. Some problems with

migration of tapes containing thousands of files. • Pnfs scans, cleanups, problem resolutions. Resolved all inconsistencies. All

files have been taken care of. New pnfs scan of general purpose MSS was done. Reverse scan was done for the first time. Found some problems with script. Fixing it.

• Answering user’s and administrator’s questions, resolving problems• Fixing bugs

– Set tape readonly of CRC readback check fails in mover code.– Modifications to mover to better process some error conditions

• System updates and upgrades– Updated code for all systems– Upgraded enstore and pnfs DBs to PstgerSQL 8. Use online backups.


Project Milestones (continued)• ENCP Fixes, problem resolutions.

– Investigated a problem with corruption of files > 4GB written using direct IO on XFS. This is XFS problem. Works well if direct IO is not used.

– Fixed a bug allowing writing the same file several times from dCache.– Encp 3_5 was cut.– Added the ability for encp to detect when a read would exceed the quota.

• Small Projects.– Implementation of reverse file scans. Implemented, in production. Modification of

pnfs scan script.– Syncronize “at movers” list with real tape state. Not started.– Modification of encp to accept a directory path for dcache files. This is to reduce a

load on pnfs server. Done– Helping Vanderbilt University to resolve problems. Ongoing– Enstore code cleanup. Ongoing– Preparing for OS, Python upgrades. Low priority– Conversion to PostgreSQL 8. Done– Pnfs agent to provide an encp access to pnfs name space without mounting pnfs and

as a 1st step towards pnfs-less Enstore. In progress– Reverse pnfs scans. Done.


Project Milestones (continued)

• Tape Migration Support– ISA is migrating file. Developers provide support and fixes– Migration of deleted files. Done– Migration of 9940A tapes to 9940B tapes. Started, 95 tapes migrated. In ~1 month.

Migration is slow, runs at the lowest priority, can run faster if needed.– CDF wanted to compact data on partially written tapes and have the capability in

future to write several file families to the same tape. Enstore already has this by modification of volume family in the volume DB. Need some code modifications but it can be done later. No need to wait for CDF.

• Distributed tape operations– Multiple copy. Write part works and can be (in principle) used. Reads need more

work.– Solutions for Federation worked out. Prepared necessary changes. Can be done fast

if requested.– Administrative enstore web access. Choosing tools and solutions for web server

side interface, enstore interface. On hold.


Project Milestones (continued)• Open Science Grid Data

– No activity so far

• Next generation tape– Participation in tape strategy. Ongoing

• Second generation monitoring– Generate plots, add web pages upon request. Ongoing– Transfer rate plots. Improved, put on aseparate web page.– Plots of tape usage per file family on a separate web page.– New approach to data presentation on demand. On hold.

• Not covered in GDM list– University of Vanderbilt Estore consultations. Ongoing

– SALK institute (CA) is interested in archiving retinal data to Enstore. Had a meeting. Set up access. Transfer tests were done.

• SRM-Enstore in progress


Effort Profile

• 3.5 people work on Enstore project.• Support and maintenance requires 2 FTE. • Distributed tape opOther main activity is concentrated on distributed tape

operations. 1.5 FTE works now on the project. Requires 2 FTE. New hire started on 04/25/2005


Risks

• I do not see or foresee any technical risks. The system is stable. We test new technologies before making decision to use them.

08/30/05gdm project presentation lower storage summary of activity on 8/30/2005

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